Students Handbook. B.Tech. Mechanical Engineering. Semester-V

Transcription

1 Students Handbook B.Tech Mechanical Engineering Semester-V Department of Mechanical Engineering Ambala College of Engineering and Applied Research, Ambala (Affiliated With) Kurukshetra University, Kurukshetra

2 Vision of the Institute To become a source of technology and start an Incubation Centre for entrepreneurs resulting in this region developing into a vibrant industrial hub with many startup companies dealing with new technology. Mission of the Institute 1. To impart quality engineering education to students through quality teaching, hands on training, and applied research in practical and product oriented projects. 2. To impart such education those passing out students are ready with good theoretical and practical knowledge to suite the current need of industry. 3. To expose students to applied research, especially the fact that research does not require much money but does require great persistence. 4. To sow the seed of entrepreneurship in them so that our engineers become job providers and not job seekers. 5. To train students as a complete person through extracurricular activities and with an exposure to a transparent system based on ethics so that they believe that a successful institution and a successful business can be run with ethics without corruption. Mechanical Engineering Deptt. Vision of the Department To develop the next generation of professionals in Mechanical Engineering by providing best of teaching and practical learning approach. Mission of the Department The mission of the ACE Mechanical Engineering Department is to I. Constantly strive to improve instructive methods employed in delivering the Mechanical Engineering academic programmes. II. Prepare effective, responsible and skilled engineering professionals. III. Participate in research and development activities for contribution in industrial up gradation and strengthening the industry - institute relationship. IV. Cultivate the spirit of entrepreneurship among students.

3 PEOs of Mechanical Engineering Department PEO-1, To make students capable of applying the fundamentals of mathematics, basic sciences, humanities, technical arts and engineering sciences in solving engineering problems. PEO-2, To develop analytical skills in mechanical engineering students for solving engineering problems. PEO-3, To impart knowledge to students about design methodologies in thermo fluids, materials and engineering systems using latest design tools. PEO-4, To make the students familiar about latest technologies in all mechanical engineering fields for meeting societal needs in a cost effective manner. PEO-5, To encourage students to acquire managerial and entrepreneurial skills and to take innovative and research oriented projects. POs of Mechanical Engineering Department The outcomes we desire are that our graduates demonstrate: a) An ability to apply knowledge of mathematics, science, and engineering to mechanical engineering problems. b) An ability to conduct experiments, as well as to analyze and interpret data. c) An ability to design systems, components, or processes to meet desired needs. d) An ability to function on multi-disciplinary teams. e) An ability to identify, formulates, and solves engineering problems. f) An understanding of professional and ethical responsibility. g) An ability to communicate effectively with written, oral, and visual means. h) The broad education necessary to understand the impact of engineering solutions in a societal and global societal. i) Recognition of the need for and an ability to engage in life-long learning. j) Knowledge of contemporary issues. k) An ability to use modern engineering techniques, skills, and computational tools necessary for engineering practice. l) An ability to work professionally in both thermal, design and production engineering areas. m) An ability to act as Entrepreneur.

4 S. N o 1 Subjects Name I.C. Engine & Gas Turbine Code Scheme of Examination B.Tech 5 th Sem (Mechanical Engineering) Teaching Schedule (Hrs) L T P/ D Tota l Examination Schedule (Marks) Sessiona l Theor y Practical/viva -voce Total Mark s ME 301E Duratio n of Exam (Hrs) Fluid 2 Machines 3 ME E Heat Transfer Industrial Engineeri ng Machine Design 1 Steam Generatio n & Power Thermal Engineeri ng (PR) Fluid Machines (PR) Heat Transfer (PR) Industrial Engineeri ng Machine Design I (Vivavoce) Vocationa l Training 3 ME E ME 307 E ME 309 E ME 311 E ME 313 E ME 315 E ME 317 E ME 319 E ME 321 E ME 323 E Total Note: Students will be allowed to use Non-Programmable scientific calculator. However, sharing of calculator will not be permitted. Duration of theory as well as practical exams time is three hrs for all courses.

5 I.C. Engine and Gas Turbines (ME-301E) Course Educational Objectives (CEOs) :- 1. To impart knowledge to students about the internal combustion engines. 2. To make the students learn the mathematical analysis of different cycles on which these engines and gas turbine works. 3. To give knowledge to students regarding the functioning of different components of I.C. engine power plant. 4. To educate the students regarding the combustion phenomena in engines. 5. To make the students capable of evaluating the various performance parameters of the engine and doing basic engine measurements. 6. To make the students learn the working and capable of doing mathematical analysis of reciprocating compressors and gas turbines of different types. 7. To make the students aware about the pollutants from engines, their current scenario and its control methods. Course Outcomes (COs) :- i. Students will acquire the basic knowledge of the working of the engine, turbine and compressors. ii. Students will be able to solve the basic engineering problems related to engines, gas turbines and compressors and can perform experiments on engines and compressors. iii. Students will learn in detail the working of different components of I.C. engine power plant such as cooling system, lubricating system, ignition system, fuel supply system. iv. Students will gain the knowledge about the combustion phenomena of both the diesel and petrol engines and also the factors that are responsible for abnormal combustion in them v. Students will learn about the emissions from the engines, their effect on environment and health and their control methods. I.C.ENGINE AND GAS TURBINES ME 301 E L T P/D Total Theory: 100 Marks Sessional: 50 marks Duration of Exam: 03 hours UNIT 1 Heat engines; Internal and external combustion engines; Classification of I.C. Engines; Cycle of operations in four strokes and two-stroke IC engines; Wankle Engine. Assumptions made in air standard cycles; Otto cycle; Diesel cycle; Dual combustion cycle; Comparison of Otto, diesel and dual combustion cycles; Sterling and Ericsson cycles; Air standard efficiency, Specific work output. Specific weight; Work ratio; Mean effective pressure; Deviation of actual engine cycle from ideal cycle. UNIT II Mixture requirements for various operating conditions in S.I. Engines; Elementary carburetor, Calculation of fuel air ratio; The complete carburetor; Requirements of a diesel injection system; Type of injection system; Petrol injection; Requirements of ignition system; Types of ignition systems, ignition timing; Spark plugs. S.I. engines; Ignition limits; Stages of combustion in S. I. Engines; Ignition lag; Velocity of flame propagation; Detonation; Effects of engine variables on detonation; Theories of detonation; Octane rating of fuels; Pre-ignition; S.I. engine combustion chambers. Stages of combustion in C.I. Engines; Delay period; Variables affecting delay period; Knock in C.I. Engines; Cetane rating; C.I. Engine combustion chambers. UNIT III Functions of a lubricating system, Types of lubrication system; Mist, Wet sump and dry sump systems; Properties of lubricating oil; SAE rating of lubricants; Engine performance and lubrication; Necessity of engine cooling; Disadvantages of overcooling; Cooling systems; Air-cooling, Water-cooling; Radiators. Performance parameters; BHP, IHP, Mechanical efficiency; Brake mean effective pressure and indicative mean effective pressure, Torque, Volumetric efficiency; Specific fuel consumption (BSFG, ISFC); Thermal efficiency; Heat balance; Basic engine measurements; Fuel and air consumption, Brake power, Indicated power and friction power, Heat lost to coolant and exhaust gases; Performance curves;

6 UNIT IV Pollutants from S.I. and C.I. Engines; Methods of emission control, Alternative fuels for I.C. Engines; The current scenario on the pollution front. Working of a single stage reciprocating air compressor; Calculation of work input; Volumetric efficiency; Isothermal efficiency; Advantages of multi stage compression; Two stage compressor with inter-cooling; Perfect inter cooling; Optimum intercooler pressure; Rotary air compressors and their applications; Isentropic efficiency. Brayton cycle; Components of a gas turbine plant; Open and closed types of gas turbine plants; Optimum pressure ratio; Improvements of the basic gas turbine cycle; Multi stage compression with inter-cooling; Multi stage expansion with reheating between stages; Exhaust gas heat exchanger; Application of gas turbines. Recommended books Internal combustion engine by Ramalingam scitech publication Internal combustion engine by Ganeshan TMG Internal combustion engine by Mathur & Sharma Heat power engineering by Dr. V.P. Vasandhani & Dr. D.S. Kumar NOTE: In the semester examination, the examiner will set 8 questions in all, at least two question from each unit, and students will be required to attempt only 5 questions, at least one from each unit. Lecture No Lecture Topic 1. Heat Engines, Internal & External Combustion Engines, Classification of Engines. 2. Four Stroke Spark Ignition Engines & Compression Ignition Engines. 3. Two Stroke Spark Ignition Engines & Compression Ignition Engines. 4. Wankel Engine. 5. Air Standard Cycle Assumptions & Otto Cycle. 6. Diesel Cycle & dual Cycle. 7. Comparison of Otto Cycle, Diesel Cycle & Dual Cycle. 8. Sterling Cycle. 9. Ericson Cycle. 10. Air Standard Efficiency, Specific Work Output, Work Ratio, Specific Weight. 11. Mean Effective Pressure of Otto Cycle, Diesel Cycle & Dual Cycle. 12. Deviation of Actual Engine Cycle From Ideal- Petrol & Diesel Engines. 13. Mixture Requirement For S.I Engine. 14. Elementary Carburetor & Fuel-Air Ratio. 15. Complete Carburetor. 16. Requirement of Diesel Injection, Types of Injection. 17. Petrol Injection. 18. Ignition Systems- Magneto, Battery; Spark Plug. 19. Ignition Timings. 20. Ignition Limits in S.I Engines. 21. Stages Of Combustion in S.I Engine- Ignition Lag & Flame Propagation. 22. Detonation- Reasons, Effect of Engine Variables, Theory of Detonation. 23. Preignition, S.I Combustion Chambers. 24. Octane Rating. 25. Stages Of Combustion in C.I Engine, Delay Period, Variables affecting delay period. 26. Knock in C.I Engines, Cetane Rating. 27. C.I Combustion Chambers. 28. Lubricating system- Functions & Requirements. 29. Mist, Wet Sump, Dry Sump Systems.

7 30. Properties of Lubricating Oil, SAE Rating, Engine Performance & Lubrication. 31. Engine Cooling- Necessity, Cooling System- Air & Water; Radiators, Overcooling. 32. Performance of Engines. 33. Brake Power, Indicated Power, Morse Test, Heat balance, Performance Curves. 34. Brayton Cycle, Open & Closed type of Gas Turbine; Optimum Pressure Ratio. 35. Improvement of Basic Cycle, Multistage Compression, Intercooling, Reheating, Regeneration. 36. Reciprocating Air Compressor, Single stage, Multi stage, intercooling, Optimum Intercooler Pressure. 37. Compressor Calculations, Effect of Clearance, Volumetric & Isothermal Efficiency. 38. Rotary Air Compressors & Applications. 39. Pollutants & Emission control in S.I & C.I Engines. 40. Pollution Norms upto Euro IV, Alternate Fuels. TUTORIAL SHEET NO 1 1. What is a heat engine? Distinguish between External Combustion Engines and Internal Combustion Engines, giving two examples of each. 2. What are the assumptions made in deriving air standard efficiencies of thermodynamic cycles. What are its limitations? 3. Give at least ten ways in which I.C. Engine can be classified. 4. With the help of neat sketches, explain the actual sequence of events in the cylinder of a petrol engine working on a four stroke cycle. 5. Show the air-standard otto cycle on p-v and T-S diagrams. Derive an expression for air standard (thermal) efficiency of otto cycle. 6. Define mean effective pressure. Derive an expression for mean effective pressure of an otto cycle. Show the cycle on p-v and T-S diagrams. What are the numerical values for actual petrol engine. 7. In an air standard otto cycle, compression ratio is 8, pressure and temperature at the beginning of compression are 1 bar and 27º C respectively. Maximum cycle pressure is 40 bar. Calculate (i) Air standard efficiency, (ii) Maximum cycle temperature, (iii) Heat supplied per kg of air and (iv) Work done per kg of air. Show the cycle in p-v and T-S diagram and state assumptions made. For Air, Take Cv = KJ/Kg K and γ = Explain with sketches the working of Wankel Engine. Discuss its advantage and disadvantages with respect to conventional I.C. Engine. TUTORIAL SHEET NO 2 1. Draw valve timing diagrams of a four stroke CI engine and explain the reasons for keeping these timings. 2. An ideal diesel engine has a diameter of 150 mm and stroke of 200 mm. The clearance volume is 10% of the stroke volume. Cut off is at 6% of stroke. Determine Compression ration and air standard efficiency. Take γ = Compare S.I. Engine with C.I. Engine. Give at least 20 points. 4. Derive an expression for the efficiency of a dual combustion cycle. Show the cycle on p-v and T-S diagram. 5. An engine working on a dual combustion cycle has a pressure of 1 bar and 50ºC before compression. The air is then compressed isentropically to 1/15 th of the original volume. The max. pressure is twice that of the pressure at the end of isentropic compression. Take cut off ration as 2.0. Determine the temperature at the end of each process, the ideal efficiency and mean effective pressure of the cycle. Take Cp = KJ/Kg K, Cv = KJ/Kg K and γ = In a diesel engine air standard cycle analysis, the compression ratio is 14:1, pressure at the end of suction stroke is 0.95 bar, the expansion ratio is 5:1, determine, (i) Pressure at the beginning and end of the stroke, (ii) the mean effective pressure, (iii) the power developed if bore is 25 cm and stroke is 40 cm, engine is 4 stroke and runs at 1000 rpm, (iv) Air Standard efficiency. For air, Cp = KJ/Kg K and γ = 1.4.

8 TUTORIAL SHEET NO 3 1. In an otto cycle, air at 0.95 bar and 290 K is compressed isentropically until the pressure is 14 bar. Heat is added at constant volume till the pressure rises to 38 bar. Calculate (i) Compression Ration, (ii) Max. Cycle Temperature, (iii) Heat Supplied, (iv) Air Standard Efficiency, (v) Mean effective pressure. Take Cv = KJ/Kg K, Ro = KJ/Kg mole K. 2. Explain the neat sketches the working of a two stroke S.I. Engine and discuss its advantage and disadvantages with a four stroke S.I. Engine. 3. Explain the reasons for the discrepancy between the actual thermal efficiency of a petrol engine and the value predicted by air standard otto cycle analysis. 4. Derive an expression for air standard efficiency and MEP of a diesel cycle. Show the cycle on p-v and T-S diagrams. What are the actual values of MEP for C.I. Engines. 5. In an air standard diesel cycle, the compression ratio is 15:1, the heat transfer is 1465 KJ/Kg of air. Find the pressure and temperature at the end of each process and determine the cycle efficiency. What is the mean effective pressure of the cycle if the inlet conditions are 1 bar and 300 K. Assume suitable data for specific heat values. 6. Derive an expression for MEP of a dual combustion cycle. 7. A single cylinder four stroke diesel engine working on dual combustion cycle has a compression ration of 15:1. The engine draws in air at 1 bar and 27ºC and maximum volume is twice that at constant pressure. Determine (i) The pressure ration of constant volume process, (ii) the cut off ration, (iii) The thermal efficiency of ideal cycle. Take Cp= KJ/Kg K, Cv = KJ/Kg K and γ = Compare the efficiencies of otto, diesel and dual cycles for (i) same compression ratio and heat input, (ii) same max pressure and heat input, (iii) same max. pressure and temperature. 9. Two engines are operating on otto and diesel cycles respectively with the following cycles: Max. Temp. = 1500 K Exhaust Temp. = 700 K Ambient Conditions = 1 bar, 300 K Compare the compression ratio, max. pressure and efficiencies of two cycles. TUTORIAL SHEET NO 4 1. What are the mixture requirements for various operating conditions in S.I. engine. Explain with the help of graph between vehicle speed and air-fuel ratio. 2. Define: air-fuel ratio, fuel-air ratio, stoichometric ratio, equivalence ratio, power mixture, economy mixture, accelerating conditions, idling conditions, starting and warm up. 3. What is the function of a carburetor in an S.I. Engine? Explain with a sketch the operation of a simple float type carburetor. 4. What are the limitations of a simple carburetor in meeting the A/F ratio requirements of a petrol engine under all operating conditions. Explain how these limitations can be overcome by an appropriate modification. 5. A simple jet carburetor is required to supply 6 kg of air per minute and 0.45 kg of petrol of density 740 Kg/m³. The air is initially at bar and 27º C. Calculate the throat diameter of the choke for a flow velocity of 91m/s. Velocity coefficient = 0.8. If the pressure drop across the fuel metering orifice is 0.75 of that at choke, calculate orifice diameter assuming Cd = Explain with a neat sketch, the construction and working of any complete carburetor (SU, Carter, Solex, Zenith). 7. Describe the idling system of a carburetor. Why a rich mixture is required for idling? 8. Describe the accelerating system of a carburetor. Why a rich mixture is required for maximum power? 9. What is detonation? Explain the phenomena of detonation in case of S.I engines. 10. Discuss the effect of compression ratio, ignition advance, engine load, engine size, location of spark plug on detonation in S.I Engines. TUTORIAL SHEET NO 5 1. What is petrol injection? What are its advantages and disadvantages? 2. What are the disadvantages of a carburetor used in S.I. Engine? How are these overcome by a multi-point fuel injection system? 3. Explain continuous injection system and timed injection system. 4. What are the requirements of a diesel fuel injection system?

9 5. Describe with sketches (i) Air Injection, (ii) Solid Injection (I) Individual pump and injector or jerk pump system, (II) Common Rail System, (III) Distributor System, (IV) Unit Injector. Discuss advantages and disadvantages of each system. 6. Describe the working of Bosch fuel injection pump with injector. Give sketches. 7. Describe different types of injection nozzles and discuss their advantages and disadvantages. 8. A petrol engine consumes 7.5 kg of petrol per hour. The specific gravity of the fuel is The air intake temperature is 25º C. The air fuel ratio is 15. The choke tube has a diameter of 22 mm. Calculate the diameter of the fuel jet of a simple carburetor. Top of the jet is 4 mm above the petrol level in the float chamber. Take coefficient of discharge as 0.82 and 0.7 for air and fuel respectively. Atomspheric pressure = bar. 9. Why there is maldistribution in multi-cylinder engines? Why richer mixture is required in such engines? 10. Describe the following systems of a carburetor: (I) Main metering System (II) Idling System (III) Economiser or power enrichment system (IV) Acceleration pump system (V) Choke. Derive an expression for fuel air ratio of a carburetor assuming compressible isentropic flow of air. TUTORIAL SHEET NO 6 1. Why cooling is required in I.C engines. Describe thermo-syphon cooling system with the help of neat sketch. 2. Discuss the wet sump and dry sump lubrication system with the help of neat sketch. 3. Discuss the various stages of combustion in case of S.I. Engine with the help of pressure-crank diagram. 4. During a test on the four cylinder, four stroke oil engine the following data were recorded: bore= 10 cm, stroke = 12 cm, speed = 1200rpm, brake torque = 120 Nm, fuel consumption = 5kg/hr, calorific value of fuel = 42 MJ/kg, Pressure drop across orifice is 4.6 cm of water, ambient temperature and pressure are 17 C and 1 bar respectively. Air flow is measured by means of a 5 cm diameter orifice having coefficient of discharge 0.6. Calculate : Brake thermal efficiency, brake meaneffective pressure and volumetric efficiency based on free air condition. 5. A 4-cylinder, 4-stroke petrol engine 6 cm bore and 9 cm stroke was tested at constant speed. The fuel supply was fixed to 0.13 kg/ min and plugs of four cylinders were successively short-circuited without change of speed. The power measurement were as follows: With all cylinders working = KW, with No1 cylinder cut off = KW, with No 2 cylinder cut off = KW, with No 3 cylinder cut off = KW, with No 4 cylinder cut off = KW. Find : Indicated power of engine, frictional power of the engine, mechanical efficiency and relative efficiency on I.P basis assuming clearance volume 65 cu cm. 6. What are the disadvantages of overcooling in I.C Engines? 7. Write note on the following:- 1. Lubricant properties and SAE Rating. 2. Radiators and function of pressure cap in radiator. 3. Advantages and disadvantages of air cooling system. 8. During the Morse test on 4-cylinder, 4-stroke petrol engine, the following readings are taken: Diameter of cylinder = 8cm, Stroke length = 10cm, Speed = 3000 rpm, Load on hydraulic dynamometer = 160 N, Dynamometer constant = 20420, fuel consumption = 8 kg/hr, C.V. of fuel used = kj/kg. By shortening the spark plug of each cylinder successively without change of speed the corresponding B.Ps. of the engine are 16.5, 16, 15.6, 17.6 respectively. Determine : Brake power, Brake mean effective pressure, brake thermal efficiency and mechanical efficiency. TUTORIAL SHEET NO 7 1. A single cylinder reciprocating compressor runs at 150 rpm and delivers 5m 3 of free air per minute.(p= 1bar and T= 300 K at point 1). Maximum delivery pressure is 6 bar. Law of compression P.V 1.3 = C. Clearance 5% of stroke. Calculate temperature of air at inlet to receiver, volumetric efficiency, Volume of air per stroke sucked, power of motor. Dimensions of cylinder if L/D = Estimate the work done by a two stage reciprocating single acting air compressor to compress 2.8 m 3 of air per minute from 1.05 bar and 10 C to a final pressure of 35 bar. The intermediate receiver cools the air to 30 C and 5.6 bar pressure. Take n= 1.4

10 3. A single stage double acting air compressor has a free air delivery of 14 m 3 / min at bar and 15 C. The pressure and temperature during induction is 0.95 bar and 32 C. The delivery pressure is 7 bar and index for compression and expansion is P.V 1.3 = C. Clearance Volume is 5% of swept Volume. Calculate Indicated power required, Volumetric Efficiency and Isothermal Efficiency. 4. A gas turbine plant works on a pressure ratio of 5:1. Initial temperature is 300 K and maximum temperature is 1000 K. Isentropic efficiency of turbine is 0.88 and that of compressor is For air take γ= 1.4 Cp=1.005 kj/ kg K. Effectiveness of heat exchanger is Calculate net work done, heat supplied and efficiency. Take 1 kg of working substance. TUTORIAL SHEET NO 8 1. In a gas turbine plant, operating on joule cycle, maximum and minimum temperatures are 825 C and 27 C respectively. The pressure ratio 4.5. Calculate the specific work output, cycle efficiency and work ratio. Assuming isentropic efficiency of compressor as 85% and turbine 90%. Find out the heat rate in kj/kw- Hour. If the rating of turbine is 1300 KW, what is the mass flow in Kg/Sec. Neglect the mass flow of fuel. Given: Cp=1.005 kj/ kg K. 2. Determine the efficiency of gas turbine plant fitted with heat exchanger of 75% effectiveness. The pressure ratio is 4:1 and compression is carried out two stages of equal pressure ratio with inter-cooling back to initial temperature of 290 K. The maximum temperature is 925 K. The turbine isentropic efficiency is 88% and each compressor has isentropic efficiency of 85%. For air take γ= 1.4 Cp=1.005 kj/ kg K. 3. In a simple gas turbine plant air enters the compressor at 1 bar and 27 C and leaves at 6 bar. It is the heated in combustion chamber to 700 C and then enters the turbine to expand to 1 bar. The isentropic efficiency of compressor is 0.80 and turbine is 0.85and the combustion efficiency is The fall in pressure through combustion chamber is 0.1 bar. Find: thermal efficiency, work ratio, air rate in Kg/KW, specific fuel consumption and air fuel ratio. 4. A gas turbine unit receives air at 100 KPa and 300 K and compresses it adiabatically to 620 KPa with efficiency of compressor 80%. The fuel has heating value of KJ/Kg and fuel/air ratio is kg fuel per kg of air. The turbine internal efficiency is 90%. Calculate the compressor work, turbine work and thermal efficiency. 5. A closed cycle gas turbine consist of 2 stage compressor and a 2 stage turbine. All the components are mounted on same shaft. The temperature and pressure at the inlet of first stage compressor are 2 bar and 250 C. The maximum cycle temperature and pressure are limited to 850 C and 8 bar. A perfect intercooling is used between the two compressors and a reheater is used between the two turbines. Gases are reheated in the reheater to 850 C before entering into I.P turbine. Assuming the compressor and turbine efficiencies as Find: cycle efficiency without regenerator, with regenerator if effectiveness is For air take γ= 1.4 Cp=1 kj/ kg K. If I.P developed by turbine plant is 310 KW, find the mass of fluid circulated. Air is used as working fluid in the cycle.

11 Course Educational Objectives (CEOs) : - Fluid Machines (ME-303E) 1. To make students aware about concept of applications of fluid power. 2. To impart knowledge on different types of hydro turbines. 3. To make students capable of doing basic design for different types of turbines 4. To educate the students about working of hydraulic turbines. 5. To make the students gain knowledge of model analysis. 6. To impart knowledge to students about different fluid pumps 7. To make students learn about working and losses in centrifugal and reciprocating pumps. 8. To give knowledge to students about different other applications of fluid power. Course Outcomes (COs) : - i. Student will acquire the knowledge about basic applications of fluid power. ii. Student will get familiar with the turbines and pumps and can perform experiments on that. iii. Students will be able to select the type of turbine, formulate the basic design of hydraulic machines. iv. Students will be able to solve problems related to hydraulic turbines and pumps FLUID MACHINES ME 303 E L T P/D Total Theory: 100 Marks Sessional: 50 marks Duration of Exam: 03 hours UNIT I Impact of jet stationary and moving flat and curved plates, Force on series of vanes, Radial vanes, Vortex motion, Free and forced vortex, jet propulsion of ships Units and dimensions; Dimensional homogeneity; Dimensional analysis methods; Ray Leigh and Buckingham methods, Applications and limitations of dimensional analysis Dimensionless numbers, Similitude laws. UNIT II Introduction; Development of hydraulic turbines; Components of hydropower plant; Classification of turbines; Surge tank and its type. Pelton turbine, Its components, Number and dimension of buckets, Speed ratio, Jet ratio, Energy conversion, Condition for maximum efficiency; Design considerations. Governing etc. Francis turbine, its components, working principles. Draft tube, Types of draft tube, Design considerations; Outward vs. Inward flow reaction turbines, Introduction to Deriaz turbine, Evolution of axial flow turbines, Kaplan turbine, Operation at off-design loads, Governing etc. Unit quantities, Specific speed, Runway speed, Characteristics of turbines, UNIT III Introduction, Classification, Components, Principle of working, various heads, Energy conversion, Euler s head and its variation with vane shapes. Effect of finite number of vanes, Losses and efficiencies, Minimum starting speed, Limitation of suction lift, Net Positive Suction Head (NPSH); Multistage pumps, Specific speed and performance. Working principles, Classification, Components, Discharge, Discharge slip, Power input, Indicator diagram, Effect of friction, Acceleration and pipe friction, Maximum speed, Air vessels, Comparison with centrifugal pumps. Model testing of pumps. UNIT IV Cavitations and its effects, Cavitation parameters, Detection and Prevention of cavitations. Model testing of turbine Propeller pump, Jet pump, Airlift pump, Gear pump, Screw pump, Vane pump, Radial piston pump, Submersible pump, Pump problems Hydraulic accumulators, Hydraulic intensifier, Hydraulic lift, Hydraulic crane. Hydraulic coupling, Torque converter, Hydraulic ram.

12 Recommended books Fluid mechanics and machinery by S.K.Aggarwal TMG Fluid mechanics & fluid power engineering by D.S kumar, Katson publisher Fluid mechanics and Hydraulic machine by S.S rattan, Khanna publisher Introduction to fluid mechanics and machinery by Som and Bishwas, TMH NOTE: In the semester examination, the examiner will set 8 questions in all, at least two question from each unit, and students will be required to attempt only 5 questions, at least one from each unit. S.N. LECTURE TOPIC 1 Units and dimensions; Dimensional homogeneity 2 Dimensional analysis methods; Ray Leigh 3 Buckingham methods 4 Applications and limitations of dimensional analysis 5 Dimensionless numbers, Similitude laws. 6 Impact of jet stationary 7 Impact of jet moving flat 8 Impact of jet curved plates 9 Force on series of vanes 10 Radial vanes 11 jet propulsion of ships 12 Vortex motion 13 Test 1 14 Introduction; Development of hydraulic turbines; Components of hydropower plant; 15 Classification of turbines; Surge tank and its type 16 Pelton turbine, Its components, Number and dimension of buckets, Speed ratio, Jet ratio, Energy conversion, Condition for maximum efficiency 17 Design considerations. 18 Francis turbine, its components, working principles. Draft tube, Types of draft tube 19 Outward vs. Inward flow reaction turbines 20 Evolution of axial flow turbines 21 Kaplan turbine 22 Unit quantities, Specific speed, Runway speed 23 Characteristics of turbines, Governing of turbine 24 Test 2 25 Centrifugal pump, work done, heads and efficiencies, min speed 26 Multistage pump, specific speed 27 Cavitation, NPSH 28 Reciprocating pump, slip 29 Variation of velocity and acceleration in suction and delivery pipe 30 Effect of variation of velocity in suction & delivery pipe, air vessels 31 Test 3 32 Hydraulic press & accumulators 33 Hydraulic intensifier, Hydraulic lift, Hydraulic ram 34 Hydraulic crane. Hydraulic coupling 35 Torque converter, Airlift pump 36 Gear pump 37 revision 38 revision TUTORIAL SHEET NO 1 1. A jet of water having a velocity of 15 m/s, strikes a curved vane which is moving with a velocity of 6 m/s in the same direction as that of the jet at inlet. The vane is so shaped that the jet is deflected through 135. The

13 diameter of the jet is 150 mm. Assuming the vane to be smooth, find (i) the force exerted by the jet on the vane in the direction of motion, (ii) power of the vane, and (iii) efficiency of the vane 2. A jet of water having a velocity of 30 m/s strikes a series of radial curved vanes mounted on a wheel which is rotating at 300 rpm. The jet makes an angle of 30 with the tangent to wheel at inlet and leaves the wheel with a velocity of 4 m/s at an angle of 120 to the tangent to the wheel at outlet. Water is flowing from outward in a radial direction. The outer and inner radii of the wheel are 0.6 m and OJ m respectively, Determine: (i) vane angles at inlet outlet, (ii) work done per sec per kg of water, and (iii) efficiency of the wheel. 3. A jet of water of diameter 50 mm strikes a fixed plate in such a way that the angle between the plate and the jet is 30. The force exerted in the direction of the jet is N. Determine the rate of flow of water. 4. A 7.5 cm diameter jet having with a velocity of 30 m/s strikes a flat plate, the normal of which is inclined at 45 to the axis of the jet. Find the normal pressure on the plate: (i) when the plate is stationary, and (ii) when the plate is moving with a velocity of 15 m/s and away from the jet. Also, determine the power and efficiency of the jet when the plate is moving. 5. A jet of water of diameter 50 mm, having a velocity of 20 m/s strikes a curved vane which is moving with a velocity of 10 m/s in the direction of jet. The jet leaves the vane at an angle of 60 to the direction of motion of vane at outlet. Determine: a. The force exerted by the jet on the vane in the direction of motion. b. Work done per second by the jet. 6. A jet of water having a velocity of 40 m/s strikes a curved vane, which is moving with a velocity of 20 m/s. The jet makes an angle of 30 with the direction of motion of vane at inlet and leaves at an angle of 90 to the direction of motion of vane at outlet. Determine the vane angles at inlet and outlet so that the water enters and leaves the vane without shock TUTORIAL SHEET NO 2 1. A jet of water having a velocity of 20 m/s strikes a curved vane which is moving with a velocity of 9 m/s. The vane is symmetrical and is so shaped that the jet is deflected through 120. Find the angle of the jet at inlet at inlet of the vane so that there is no shock. What is the absolute velocity of the jet at outlet in magnitude and direction and the work done per second per unit weight of water striking? Assume the vane to be smooth. 2. A jet of water having a velocity of 40 m/s strikes a curved vane, which is moving with a velocity of 20 m/s. The jet makes an angle of 30 with the direction of motion of vane at inlet and leaves at an angle of 90 to the direction of motion of vane at outlet. Draw the velocity triangles at inlet and outlet and determine the vane angles at inlet and outlet so that the water enters and leaves the vane without shock. 3. A jet of water of diameter 75mm strikes a curved plate at its center with a velocity of 20 m/s. The curved plate is moving with a velocity of 8 m/s in the direction of the jet. The jet is deflected through an angle of 165. Assuming the plate smooth find: (i) Force exerted on the plate in the direction of jet, (ii) Power of jet and (iii) Efficiency of jet. 4. The drag force exerted by a flowing fluid on a solid body depends upon the length of the length (L), velocity of flow (V), density of fluid (p) and viscosity. Find an expression for drag force using Buckingham's-n- theorem 5. The variables containing the motion of a floating vessel through water are the drag force F, the speed V, the length L, the density p, dynamic viscosity of water and acceleration due to gravity g. Derive an expression for F by dimensional analysis 6. The drag force exerted by a flowing fluid on a solid body depends upon the length of the body L, velocity of flow V, density of fluid p and viscosity j.l. Find an expression for drag force using Buckingham's-n- theorem TUTORIAL SHEET NO 3 1. Obtain an expression for the work done per second by water on the runner of a Pelton wheel. 2. Draw inlet and outlet velocity triangles for a Pelton Turbine and indicate the direction of various velocities. 3. Obtain an expression for unit speed, unit discharge and unit power for a turbine. 4. A turbine develops kw S.P. when running at 200 rpm. The head on the turbine is 40 m. if the head on the turbine is reduced to 25 m, determine the speed and power developed by the turbine. 5. A turbine is to operate under a head of 30 m at 300 rpm. The discharge is 10 m 2 / s. if the efficiency is 90 %, determine : (i) specific speed of yhe machine, (ii) power generated, and (iii) types of turbine. 6. A Pelton wheel has a mean bucket speed of 35 m/s with a jet of water flowing at the rate of 1 m 3 / s under a

14 head of 270 m. the buckets deflect the jet through an angle of Calculate the power delivered to the runner and the hydraulic efficiency of the turbine. Assume coefficient of velocity at TUTORIAL SHEET NO 4 1. A Pelton wheel is having a mean bucket diameter of 1 m and is running at 1000 rpm. The net head on the Pelton wheel is 700 m. If the side clearance angle is 15 and the discharge through nozzle of 0.1 m 3 /see, find: a.power available at the nozzle. b.hydraulic efficiency of the turbine 2. An inward flow reaction turbine has an external diameter of 1 m and it's breadth at inlet is 200 mm. If the velocity of flow at inlet is 1.5 m/s, find the mass of water passing through the turbine per second. Assume 15% of the area of flow is blocked by blade thickness. If the speed of the runner is 200 rpm and guide blades make an angle of 150 to the wheel tangent, draw the inlet velocity triangle and find: (i)the runner vane angle at inlet, (ii) velocity of wheel at inlet, (iii) the absolute velocity of water leaving the guide vanes, and (iv) the relative velocity of water entering the runner blade. 3. The internal and external diameters of an outward flow reaction turbine are 2 m and 2.75 m resp., The turbine is running at 250 rpm. The rate of flow of water through the turbine is 5 m 3 /sec. The width of the runner is constant at inlet and outlet and is equal to 250 mm. The head of the turbine is 150 m. Neglecting the thickness of the vane and taking discharge radial at outlet determine: a. Vane angle at inlet and outlet. b. Velocity of flow at inlet and outlet. 4. The following data is given for Francis Turbine: Net Head= 70m, speed = 600rpm, shaft power = KW, 110= 95%, flow ratio=0.25, breadth ratio = 0.1, outer dia of the runner = 2 * inner dia of runner. The thickness of vanes occupies 10% of the circumferential area of the runner. Velocity of flow is constant at inlet and outlet and discharge is radial at outlet. Determine (i) guide blade angle, (ii) runner vane angles at inlet and outlet, (iii) dia of runner at inlet and outlet, (iv) width of wheel at inlet 5. A Kaplan turbine working under a head of 25m develops 16000KW shaft: power. The outer dia of runner is 4m and hub dia is 2m. The guide blade angle is 350. The hydraulic efficiency and overall efficiency are 90% and 85% resp., If the velocity of whirl is zero at outlet, determine runner vane angles at in let and outlet and speed of turbine. 6. Derive an expression for maximum efficiency of the Pelton Wheel. TUTORIAL SHEET NO 5 1. Derive an expression for the head lost due to friction in suction and delivery pipes. 2. Define indicator diagram. Prove that area of the indicator diagram is proportional to the work done by the reciprocating pump. 3. Derive an expression for the work done per second in case of single-acting reciprocating pump. 4. Derive an expression for the head lost due to friction in the delivery pipe of a reciprocating pump with and without an air vessel. 5. Show from first principle that the work saved, against friction in the delivery pipe of a single-acting reciprocating pump, by fitting an air vessel is 84.8% while for a double-acting reciprocating pump the work saved is only 39.2%. 6. Derive an expression for the work done by the impeller of a centrifugal pump on water per second per unit weight of water. 7. Define Net Positive Suction Head (NPSH) and derive its expression. TUTORIAL SHEET NO 6 I. A centrifugal pump having outer diameter equal to two times of inner diameter and running at 1000 rpm works against a total head of 40m. The velocity of flow through the impeller is constant and equal to 2.5 m/s. The vanes are set back an angle of 40 0 at outlet. If the outer diameter of the impeller is 500 mm and width at outlet is 50 mm, determine: Vane angle at inlet, manometric efficiency, Work done by impeller on water/ sec.

15 2. A centrifugal pump is running at 1000 rpm. The outlet vane angle of the impeller is 30 0 and the velocity of flow is 3 m/s. The pump is working against a total head of 30 m and the discharge through the pump is 0.3m 3 /sec. If the manometric efficiency of the pump is 75%, determine (i) the diameter of the impeller (ii) the width of the impeller at outlet 3. A three stage centrifugal pump has impeller 40 cm in diameter and 2.5 cm wide at outlet. The vanes are curved at the outlet at 30 and reduce the circumferential area by 15 %. The Manometric efficiency is 85 % and the overall efficiency is 75 %. Determine the head generated by the pump when running at rpm. And discharging O.06m 3 /s. Find the shaft power also. 4. A single acting reciprocating pump running at 30 rpm delivers m3/s of water. The diameter of the piston is 25 cm and stroke length 50 cm. Determine: (i) theoretical discharge of the pump. (ii) Coefficient of discharge, and (iii) Slip and % slip of the pump. 5. A single acting reciprocating pump is to raise a liquid of density 1200 kg/m"' through a vertical height of 11.5 m from 2.5m below pump axis to 9 m above it. The plunger moves with stroke 225mm. The suction and delivery pipes are 75mm dia.and 3.5 m and 13.5 m long resp. There is a large air vessel placed on the delivery pipe near the pump axis. But there is no air vessel on the suction pipe. If the separation takes place at 8.29 N/cm 2 below atmospheric pressure, find: maximum speed, with which the pump can run without separation taking place and: Power required to drive the pump, if f = O.02. Neglect slip for the pump. 6. A single acting reciprocating pump has a plunger of 100 mm diameter and a stroke length 200 mm. The centre of the pump is 3 m above the water level in the sump and 20 m below the water level in a tank to which water is delivered by the pump. The diameter and length of suction pipe are 50 mm and 5 m while of the delivery pipe are 40 mm and 30 m resp., Determine the maximum speed at which the pump may be run without separation, if separation occurs at N/cm 2 below the atmospheric pressure. Take atmospheric pressure head = 10.3 m of water. TUTORIAL SHEET NO 7 1. Explain the working principle of a Hydraulic Press 2. Define the term, Hydraulic Accumulator. Derive an expression for the capacity of a hydraulic accumulator. 3. Explain the working principle of a Hydraulic Ram. Derive an expression for the efficiencies of the hydraulic ram. 4. What is the difference between fluid coupling and torque converter? Explain the torque converter with a neat sketch. 5. Explain with neat sketch, the principle and working of the following hydraulic devices a. Hydraulic Lift b. Hydraulic Crane c. Hydraulic Coupling d. Hydraulic torque converter e. Air lift pump f. Gear Pump 6. In a hydraulic coupling, the speeds of the driving and driven shaft are 800 rpm and 780 rpm, resp., Find: (i) The efficiency of the hydraulic coupling and (ii) The slip of the coupling TUTORIAL SHEET NO 8 1. A hydraulic press has a ram of 300 mm diameter and a plunger of 50 mm diameter. Find the weight lifted by the hydraulic press when the force applied at the plunger is 40 N. 1. A hydraulic press has a ram of 150 mm diameter and plunger of 30 mm. The stroke of the plunger is 250 mm and weight lifted is 600 N. If the distance moved by the weight is 1.2 m in 20 minutes, determine: (a) the force applied on the plunger, (b) power required to drive the plunger, and (c) number of strokes performed by the plunger 2. The water is supplied at the rate of 30 litres per second from a height of 4 m to a hydraulic ram, which raises 3 litres per second to a height of 18m from the ram. Determine D' Aubuisson's and Rankine's efficiencies of the hydraulic ram. 3. A hydraulic lift is required to lift a load of98.1 kn through a height of 12 m, once in every 100 seconds. The speed of the lift is 600 mm/s. Determine:

16 (a) Power required to drive the lift, (b) working period of lift in seconds, and (c) idle period of the lift in seconds. 5. An accumulator has a ram diameter of 250 mm a lift of 8m. The total weight on accumulator is 70 kn. The packing friction is 5% of the load on the ram. Find the power delivered to the machine if ram falls through the full height in 100 sec and at the same time the pumps are delivering m 3 /sec through the accumulator. 6. The efficiency of a hydraulic crane, which is supplied water under a pressure of 70 N/cm 2 for lifting a weight through a height of 10 m, is 60%. If the diameter of the ram is 150 mm and velocity ratio 6, find (a) The weight lifted by the crane (b) The volume of water required in liters to lift the weight

17 ME 305 E HEAT - TRANSFER L T P/D Total Theory: 100 Marks Sessional: 50 marks Duration of Exam: 03 hours UNIT I Definition of heat; Modes of Heat Transfer; Basic Laws of heat transfer, Electrical Analogy of heat conduction; Conduction through composite Walls; Overall heat transfer coefficient. The general conduction equation in Cartesian, cylindrical and spherical coordinates Steady one dimensional heat conduction without internal heat generation; The plane slab; The cylindrical shell; The spherical shell; Critical thickness of insulation; Variable thermal conductivity, Steady one dimensional heat conduction with uniform internal heat generation the plane slab; Cylindrical and spherical systems; Fins of uniform cross section; Governing equation; Temperature distribution and heat dissipation rate; Efficiency and effectiveness of fins. UNIT II Free and forced convection; Newton s law of cooling, Convective heat transfer Coefficient; Nusselt number; Dimensional analysis of free and forced convection; Analytical solution to forced convection problems; The concept of boundary layer; Hydrodynamic and thermal boundary layer; Momentum and Energy equations for boundary layer; Exact solution for laminar flow over an isothermal plate using similarity transformation; The integral approach; Integral momentum and energy equations; Solution of forced convection over a flat plate using the integral method. Analysis of free convection; governing equations for velocity and temperature fields. Relation between fluid friction and heat transfer, Reynolds analogy Dimensionless numbers; Reynolds, Prandtl Nusselt, Grashoff and Stanton Numbers and their significance, Heat transfer with change of phase; Nusselt theory of laminar film Condensation. UNIT III Theories of thermal radiation; Absorption, Reflection and transmission, Monochromatic and total emissive power; Black body concept; Planck s distribution law; Stefan Boltzman law; Wien s displacement law; Lambert s cosine law; Kirchoff s law; Shape factor; Heat transfer between black surfaces. UNIT IV Introduction; Classification of heat exchangers; Logarithmic mean temperature Difference; Area calculation for parallel and counterflow heat exchangers; Effectiveness of heat exchangers; N T U method of heat exchanger design; Applications of heat exchangers. Reference and Text books: A Text book of Heat Transfer by S.P Sukhatme, university press Heat transfer by Holman, TMG Heat and Mass transfer by D.S Kumar NOTE: In the semester examination, the examiner will set 8 questions in all, at least two questions from each unit, and students will be required to attempt only 5 questions, at least one from each unit. Lecture No Lecture Topic 1. UNIT I:-Definition of heat; Modes of Heat Transfer; Basic Laws of heat transfer, 2. The general conduction equation in Cartesian coordinates 3..The general conduction equation in cylindrical coordinates 4. The general conduction equation in spherical coordinates 5. Electrical Analogy of heat conduction; Steady one dimensional heat conduction without internal heat generation in the plane slab 6. Conduction through composite Walls; Overall heat transfer coefficient 7. Steady one dimensional heat conduction without internal heat generation in the cylindrical shell and spherical shell 8. Critical thickness of insulation; Variable thermal conductivity, 9. Steady one dimensional heat conduction with uniform internal heat generation the plane slab; Cylindrical systems

18 10. Steady one dimensional heat conduction with uniform internal heat generation the spherical systems 11. Fins of uniform cross section; Governing equation 12. Temperature distribution and heat dissipation rate in fin 13. Efficiency and effectiveness of fins. 14. Class Test 15 UNIT II:-Free and forced convection; Newton s law of cooling, Convective heat transfer Coefficient; Nusselt number 16 Dimensional analysis of free and forced convection 17 Analytical solution to forced convection problems; 18 The concept of boundary layer; Hydrodynamic and thermal boundary layer 19 Momentum and Energy equations for boundary layer 20 Exact solution for laminar flow over an isothermal plate using similarity Transformation 21 The integral approach; Integral momentum and energy equations 22 Solution of forced convection over a flat plate using the integral method. 23 Analysis of free convection; governing equations for velocity and temperature Fields 24 Relation between fluid friction and heat transfer, Reynolds analogy 25 Dimensionless numbers; Reynolds, Prandtl Nusselt, Grashoff and Stanton Numbers and their significance, 26 Heat transfer with change of phase; Nusselt theory of laminar film Condensation. 27 Class Test 28 UNIT III:- Theories of thermal radiation; Absorption, Reflection and transmission 29 Monochromatic and total emissive power 30 Black body concept; Planck s distribution law 31 Stefan Boltzman law; Wien s displacement law 32 Lambert s cosine law; Kirchoff s law 33. Shape factor 34. Heat transfer between black surfaces 35. Class Test 36. UNIT IV:- Introduction; Classification of heat exchangers 37. Logarithmic mean temperature Difference 38. Area calculation for parallel and counterflow heat exchangers 39. Effectiveness of heat exchangers 40. Effectiveness of heat exchangers continoues 41. N T U method of heat exchanger design; Applications of heat exchangers. 42. Class Test Tutorial Sheet. 1 Q.1 Derive general heat conduction equation in cylindrical co-ordinates? Q.2 Derive general heat conduction equation in spherical co-ordinates? Q.3 Define critical thickness of insulation. Derive an expression of critical thickness of insulation for cylinder.

19 Q.4 A steam main 75 mm inside diameter and 90 mm outside diameter is lagged with two successive layers of insulation. The layer in contact with pipe is 38 mm asbestos and the asbestos layer is covered with 25 mm thick magnesia insulation. The surface co-efficient for inside and outside surfaces are 227W/m 2 K and 6.8 W/m 2 K respectively. If the steam temperature is C and the ambient temp. is 35 0 C. Calculate the steady state loss of heat from steam for 60 m length of pipe. Also workout the overall co-efficient of heat transfer based on the inside and outside surfaces of the lagged stream main. Thermal conductivity values are :- Pipe material : 45W/mK, Asbestos : 0.14 W/mK,Magnesia insulation : 0.07 W/Mk Q.5 Two insulation materials A & B, in powder form,with thermal conductivity of W/mK and 0.03W/mK were purchased for use over a sphere of 40cm diameter. The material A was to form the first layer 4cm thick and material B was to be next layer 5cm thick. Due to oversight during installation whole of materials B was applied first and subsequently there was a layer formed by material A. Investigate how the conduction heat transfer would be affected Tutorial Sheet. 2 Q.1: Derive the governing differential equation for temperature distribution for a fin. Q.2: Explain fin efficiency and fin effectiveness. Also derive relationship between them for a fin insulated at the tip. Q.3: Two insulation materials A & B, in powder form,with thermal conductivity of W/mK and 0.03W/mK were purchased for use over a sphere of 40cm diameter. The material A was to form the first layer 4cm thick and material B was to be next layer 5cm thick. Due to oversight during installation whole of materials B was applied first and subsequently there was a layer formed by material A. Investigate how the conduction heat transfer would be affected. Q.4: Write a short note on Electrical Analogy of heat conduction. Q.5: A spherical shell of inner radius 5 cm and outer radius 10 cm has its inner and outer surfaces maintained at 100 C and 30 C respectively. Obtain the steady-state temperature variation in the shell if the conduction is radial and there are no heat sources or sinks. Also find the steady-state heat flux at the inner and outer surfaces. Take K= 105 W/ mk. Tutorial Sheet. 3 Q.1 Write a short note on Dimensional analysis of free and forced convection. Q.2 Write a short note on Hydrodynamic and thermal boundary layer. Q.3 Derive Momentum and Energy equations for boundary layer. Q.4 For the free convection prove the following relation Nu = CPr m C T n Where C, m, n are constants. Q.5: Air at atmospheric pressure and 200 C flowsover a plate with a velocity of 5 m/s. The plate is 15 mm wide and is maintained at a temperature of 120 C. Calculate the thickness of hydrodynamic and thermal boundary layers and the leading edge. Assume that flow is on one side of the plate. Tutorial Sheet. 4 Q.1 Derive Integral momentum and energy equations. Q.2 Derive Relation between fluid friction and heat transfer. Q.3 Write a short note on Reynolds analogy. Q.4 Explain the following Dimensionless numbers with their significance: Reynolds, Prandtl Nusselt, Grashoff and Stanton Numbers Q.5 Why is it necessary to introduce dimensionless numbers in the study of heat transfer by convection?

20 Tutorial Sheet. 5 Q.1 Explain the term Absorption, Reflection and transmission. Q.2 Explain Monochromatic and total emissive power. Q.3 Write a short note on Black body concept. Q.4 Explain Planck s distribution law. Q.5 A 100 W electric bulb has a filament temperature of 3000 C, Asumming the filament to be black, calculate (i) The diameter of the wire if the length is 2500 mm (ii) Theefficiency of the bulb if visible radiation lies in the range of wavelength from 0.5 to 0.8µ. Tutorial Sheet. 6 Q.1 Explain Kirchhoff Law, Steafen Boltzmen Law. Q.2 Define Lambert Cosine Law. Also derive a relationship between intensity of radiation and total emissive power. Q.3 Write a short note on Shape factor Q.4 Explain Wien s displacement law. Q.5 Assume the sun to a black body emitting radiation with maximum intensity at λ = 0.49 µm. Calculate (i) (ii) Surface temperature of the sun Heat flux at the surface of Sun. Q.1 Explain the classification of heat exchanger. Tutorial Sheet.7 Q.2 Derive an expression for LMTD for a counter flow heat exchanger. Q.3 Derive an expression for LMTD for a parallel flow heat exchanger. Q.4 A home air conditioning system uses a counter flow heat exchanger to cool 0.8kg/s of air from 45 0 C to 15 0 C. The cooling is accomplished by a stream of cooling water that enters the system with 0.5kg/s flow rate and 8 0 C temperature. If the overall heat transfer coefficient is 35W/m 2 K. What heat exchanger area is required?. If the same air flow rate is maintained while the water flow rate is reduced to half, how much will be the percentage reduction in heat transfer? Use effectiveness NTU approach. Q.5 A heat exchanger is required to cool kg/h of alcohol form 66 C to 40 C using kg/h of water entering at 5 C. Calculate (i) Exit temperature of water (ii) Surface area required for a) Parallel flow type b) Counter flow type heat exchanger. Tutorial Sheet. 8 Q.1 Derive an expression for effectiveness for a counter flow heat exchanger. Q.2 Derive an expression for effectiveness for a parallel flow heat exchanger. Q.3 Write the applications of heat exchangers.

21 Q.4 A home air conditioning system uses a counter flow heat exchanger to cool 0.8kg/s of air from 45 0 C to 15 0 C. The cooling is accomplished by a stream of cooling water that enters the system with 0.5kg/s flow rate and 8 0 C temperature. If the overall heat transfer coefficient is 35W/m 2 K. What heat exchanger area is required?. If the same air flow rate is maintained while the water flow rate is reduced to half, how much will be the percentage reduction in heat transfer? Use effectiveness NTU approach Q.5 The flow rate of hot and cold water streams running through a parallel flow heat exchanger at 0.2 kg/s and 0.5 kg/s respectively. The inlet temperature of hot and cold sides are 75 C and 20 C respectively. The exit temperature of hotwater is 45 C. If the individual heat transfer coefficients on both sides are 650 W/m 2 C.using NTU method, calculate (i) Mass flow rate of wter (ii) Effectiveness of the heat exchanger (i) The surface area required.

22 Course Educational Objectives (CEOs) : - Industrial Engineering (ME-307E) 1. To train the students to detect the various factors influencing the productivity of an organization and how to rectify them by using the work study. 2. To impart knowledge about the various recording techniques such as SIMO chart, two handed process chart, principle of motion economy, time study. 3. To understand the various types of organizations, their objectives and functions in global scenario. 4. To understand the product development stages and characteristics. 5. To make students able to estimate future sales forecast by using various classical as well as analytical techniques. 6. To impart basic understanding of the techniques used in industries such as JIT,MRP,Value Engineering, Supply chain management etc; Course Outcomes (COs) : - i. Students will be able to write the basic steps involved in work study and to suggest improved and economical method. ii. Students will be able to prepare various charts and diagrams used to depict the industrial activities. iii. Students will come to know about the global challenges of industries and need of re organizes their organizational structure with advanced IT based management information systems. iv. Students will be able to understand about the functions of PPC and its role in product development stages. v. Students will be able to compare the results of sales forecasting with their actual demands. vi. Students will be familiar with the JIT, MRP, MRP-II, and Supply Chain Management. INDUSTRIAL ENGINEERING ME 307 E L T P/D Total Theory: 100 Marks Sessional: 50 marks Duration of Exam: 03 hours UNIT I Introduction to work study; Method study; Basic procedure; Recording techniques (charts and diagrams); Elemental breakdown; Micro-motion studies; Therbligs; SIMO-chart; Principles of motion economy. Introduction; Objectives; technique; (time) information recording; methods of timings; Time study allowances; Work sampling technique; Performance rating and its determination PMTS; M. T. M.; Work factor. UNIT II Principles of organization, Importance and characteristics of organization, Organization theories; Classical Organization theory; Neo-Classical organization theory, Modern organization theory; Types of organization, Military or line organization, Functional organization, Line and staff organization, Committees. Objectives of PPC; Functions of PPC; Preplanning and planning; Routing; Estimating; scheduling-master schedule; Daily schedule; Gantt chart; Dispatching centralized vs. decentralized; Control; Follow up and progress reporting. Introduction; Product development; Product characteristics; Role of product development; 3Ss Standardization; Simplification and Specialization. UNIT III Introduction, Objectives and importance of sales forecasting, Types of forecasting, Methods of sales forecasting- Collective opinion method, Delphi technique, economic indicator method; Regression analysis, Moving average method, Time series analysis. Introduction, Functions of inventory; Types of inventory; Control importance and functions, Inventory costs, Factors affecting inventory control, Various inventory control models. A. B. C. analysis, Lead-time calculations. UNIT IV Introduction; Objectives; Concept and life cycle of a product and V.E.; Steps in VE., Methodology and techniques, Fast diagram, Matrix method.

23 Various concepts in industrial engineering a) WAGES AND INCENTIVES; -Concept; Types; Plans; Desirable characteristics. b) ERGONOMICS; - its importance; Man-machine work place system; Human factors considerations in system design. c) SUPPLY CHAIN MANAGEMENT; - its definition, Concept, Objectives, Applications, benefits, Some successful cases in Indian Industries. d) JIT; - Its definition, Concept, Importance, Misconception, Relevance, Applications, Elements of JIT (brief description). e) MRP;-Introduction, Objectives, factors, Guide lines, Techniques Elements of MRP system, Mechanics of MRP, MRP-II f) TIME MANAGEMENT;-Introduction, Steps of time management, Ways for saving time, Key for time saves. Reference and Text books: Production planning and control by S.Elion Modren production Management by S.S Buffa Industrial engg. and management manufacturing system by Surender kumar, Satya prakashan Essence of Supply Chain Management by R.P mohanty and S.G Deshmukh Industrial engg. and management by S Sharma and Savita sharama NOTE: In the semester examination, the examiner will set 8 questions in all, at least two question from each unit, and students will be required to attempt only 5 questions, at least one from each unit. Lecture No 1. UNIT I Introduction to work study 2. Method study; Basic procedure Lecture Topic 3. Recording techniques(charts and diagrams); 4. Elemental breakdown; Micro-motion studies 5. Therbligs; SIMO - chart;. 6. Cycle & Chrone cycle graph, Principles of motion economy 7. Work measurement, Introduction; Objectives, technique 8. (time) information, recording; methods of timings; Performance rating 9. Time study allowances; Work sampling technique; 10. Work sampling and its determination, PMTS 11. M. T. M.; Work factor 12. UNIT III Introduction, Objectives and importance of sales forecasting, Types of forecasting, 13. Methods of sales forecasting-collective opinion method, 14. Delphi technique, economic indicator method 15. Regression analysis 16. Regression analysis cont 17. Moving average method 18. Weighted Moving average method 19. Time series analysis 20. Introduction, Functions of inventory; Types of inventory 21. Inventory costs and Models 22. A. B. C. analysis, Leadtime calculations 23. UNIT II Principles of organization, Importance and characteristics of organization,

24 24. Organization theories; Classical Organization theory; Neo-Classical organization theory, Modern organization theory; 25. Types of organization, Military or line organization, Functional organization 26. Line and staff organization, Committees.Objectives of PPC; Functions of PPC; 27. Preplanning and planning; Routing; Estimating 28. scheduling-master schedule; Daily schedule; Gantt chart 29. Dispatching centralized vs. decentralized; Control; Follow up and progress reporting.introduction 30. Product development; Product characteristics; Role of product development; 3Ss Standardization; Simplification and Specialization 31. UNIT IV Introduction; Objectives; Concept and life cycle of a product and V.E 32. Steps in VE., Methodology and techniques, Fast diagram, Matrix method. 33. WAGES AND INCENTIVES; -Concept; Types; Plans; Desirable characteristics 34. ERGONOMICS; - its importance; Man-machine work place system, Human factors considerations in system design 35. SUPPLY CHAIN MANAGEMENT; - its definition, Concept, Objectives, Applications, 36. JIT; - Its definition, Concept, Importance, Misconception, Relevance, Applications, Elements of JIT (brief description). 37. MRP;-Introduction, Objectives, factors, Guide lines, Techniques Elements of MRP system, Mechanics of MRP, MRP-II Tutorial Sheet: 1 Q1 The following estimates of operation times spent on the different processes used in the manufacture of a component have been obtained: (i) Loading piece into the machine 0.20 min. (ii) Starting the machine 0.10 min. (iii) Running time of the machine at the end of which it stops automatically 4.0 min. (iv) Unloading piece from machine 0.10 min. (v) Cleaning the piece with the brush 0.10 min. (vi) Inspecting the component 0.30 min. (vii) Packing it in box 0.20 min. Draw the man and machine chart. Calculate the work cycle and the percentage of machine and operator utilization. Q2 Assume a confidence level of 95% and desired relative accuracy of ± 5%. Determine the number of observations required for the study. The work sampling method is to be used to determine the utilization of a group of drilling machines. The preliminary study indicates that the machines are utilized for about 60% of the time. Q3 A work sampling investigation was conducted to estimate the time for which the workers in plant remain idle. A total of 720 observations were made about the workers. In 45 observations the workers were found idle. If the confidence level is 95%, determine the absolute accuracy of the current estimate of the proportion of time consumed by idleness. Q4 State the meaning and use of Therblig. Sketch any ten therbligs with symbols with and their meaning and application. Tutorial Sheet: 2 Q1 Define organization. Draw the organization chart of the institute. Q2 Explain the following terms in brief: a) Routing b) Scheduling c) Route sheet d) Dispatching

25 Q3 Describe the elements of production planning and control. Q4 Describe important functions of P.P.C. Tutorial Sheet: 3 Q1 Describe the following methods of sales forecasting: (a) Moving Average method (b) Delphi Technique Q2 Sale data for previous 4 years is a variable in some firm as shown below: Years Sales (in Rs.) By the method of least squares find the trend values for each of the five years. Also estimate the annual sales for the year Q3 What are the objectives of inventory control? Derive an expression for EOQ. Q4 The requirement of a particular item in a factory is 60 unit per year. The procurement cost is Rs. 15 per order and the cost per piece is Rs The cost of carrying the inventory is 10%. Determine EOQ. Tutorial Sheet: 4 Q1 Value engineering is a powerful cost reduction tool. Justify. Q2 Discuss the importance of JIT. Also discuss its element and applications. Q3 Discuss the concept of wages and types of incentives. Q4 Discuss methodology and techniques of Value engineering. Q5 Discuss the importance of Ergonomics. What human factor need to be consider in system design.

26 Course Educational Objectives (CEOs): - Machine Design-I (ME-309E) 1. To provide basic knowledge to the students about machine design subject and design procedure. 2. To impart problem solving skills in students regarding design of basic components used in various machine parts. 3. To ensure that students learn the type of stresses induced in the mechanical members due to application of loads and various steps for designing the members. 4. To make the students acquainted with design and operation of various types of joints, shafts, levers, couplings and miscellaneous machine parts. 5. To make students competent for university and other competitive examination. Course Outcomes (COs): - i. Students will acquire the basic knowledge of concept of machine design subject. ii. Students will be able to understand the practical applications of various mechanical members in industries and machines as per requirement. iii. Students will solve the numerical based on the designing of various parts. iv. Student will completely understand the practical applications of various machine members and based upon requirements they will be able to design various parts. v. Students will be able to analyze various types of forces and stresses in machine members for designing purpose which will enhance their designing skills. vi. Students will actively take part in the subject and will discuss problems without any hesitation. Machine Design- 1 ME 309 E L T P/D Total Theory: 100 Marks Sessional: 50 marks Duration of Exam: 03 hours UNIT I Properties: Chemical, Physical, Mechanical and Dimensional; Ferrous metals, Non-ferrous metals, Plastics, Composite materials etc.; Selection of Engineering Materials. Design methodology; Design criterion based on fracture; Deformation and elastic stability design stresses; Factor of safety; Significant stress and significant strength; Stresses-concentration; Causes and mitigation; Endurance limit; Effect of concentration; Notch sensitivity; Size and surface finish; Goodman diagram; Gerber s parabola and Soderberg line. UNIT II Supports and retainment of rotating assemblies; manufacturing considerations of design, design of castings and weldments. Riveted joints for boiler shell according to I. B. R.; riveted structural joint; and riveted joint with eccentric loading; Types of welded joints; strength of welds under axial load; Welds under eccentric loading; Designation of various types of bolts and nuts, Design of bolted joints, Bolts of uniform strength, Bolted joints with eccentric loads, Design of Keys, Cotter joint and knuckle joints. UNIT III Design of shafts subjected to pure torsion; Pure bending load; Combined bending and torsion; Combined torsion; Bending and axial loads. Introduction, hand and foot levers, cranked lever, lever for a lever safety valve, Bell crank lever. Miscellaneous levers. UNIT IV Types of shaft couplings, Design of sleeve or muff coupling; Flange coupling and bush type flexible couplings. Introduction, Design of circular, oval shaped and square flanged pipe joints. Function, types of power screws, stresses in screws, design calculations.

27 References and text books: Design of machine element By Bhandari Machine design by Malvee and Hartmann, CBS publication Machine design by Sharma and Aggarwal PSG Design Data Book by PSG College of Engg PSG Publication Machine Design an integrated Approch Robert l Norton, prentice hall Fundamental of machine component design R.C Juvinnal, Johan wiley& sons NOTE: In the semester examination, the examiner will set 8 questions in all, at least two questions from each unit, and students will be required to attempt only 5 questions, at least one from each unit. Lecture No 1. UNIT I Introduction to work study 2. Method study; Basic procedure Lecture Topic 3. Recording techniques(charts and diagrams); 4. Elemental breakdown; Micro-motion studies 5. Therbligs; SIMO - chart;. 6. Cycle & Chrone cycle graph, Principles of motion economy 7. Work measurement, Introduction; Objectives, technique 8. (time) information, recording; methods of timings; Performance rating 9. Time study allowances; Work sampling technique; 10. Work sampling and its determination, PMTS 11. M. T. M.; Work factor 12. UNIT III Introduction, Objectives and importance of sales forecasting, Types of forecasting, 13. Methods of sales forecasting-collective opinion method, 14. Delphi technique, economic indicator method 15. Regression analysis 16. Regression analysis cont 17. Moving average method 18. Weighted Moving average method 19. Time series analysis 20. Introduction, Functions of inventory; Types of inventory 21. Inventory costs and Models 22. A. B. C. analysis, Leadtime calculations 23. UNIT II Principles of organization, Importance and characteristics of organization, 24. Organization theories; Classical Organization theory; Neo-Classical organization theory, Modern organization theory; 25. Types of organization, Military or line organization, Functional organization 26. Line and staff organization, Committees.Objectives of PPC; Functions of PPC; 27. Preplanning and planning; Routing; Estimating 28. scheduling-master schedule; Daily schedule; Gantt chart 29. Dispatching centralized vs. decentralized; Control; Follow up and progress reporting.introduction 30. Product development; Product characteristics; Role of product development; 3Ss Standardization; Simplification and Specialization 31. UNIT IV Introduction; Objectives; Concept and life cycle of a product and V.E

28 32. Steps in VE., Methodology and techniques, Fast diagram, Matrix method. 33. WAGES AND INCENTIVES; -Concept; Types; Plans; Desirable characteristics 34. ERGONOMICS; - its importance; Man-machine work place system, Human factors considerations in system design 35. SUPPLY CHAIN MANAGEMENT; - its definition, Concept, Objectives, Applications, 36. JIT; - Its definition, Concept, Importance, Misconception, Relevance, Applications, Elements of JIT (brief description). 37. MRP;-Introduction, Objectives, factors, Guide lines, Techniques Elements of MRP system, Mechanics of MRP, MRP-II Tutorial Sheet 1 1. How do you classify materials for engineering use? Explain in detail. 2. What are the factors to be considered for the selection of the materials for the design of machine elements? Discuss. 3. Define mechanical property of an engineering material. State any six mechanical properties, give their definitions and one example of the material possessing the properties. 4. How cast iron is obtained? Classify and explain different types of cast iron. 5. Discuss the effect of silicon, manganese, sulphur and phosphorus on cast iron. 6. Define alloy steel. Discuss the effect of nickel, chromium and manganese on steel. 7. Write short note on different types of bearing metals. 8. Explain the following terms in connection with design of machine members subjected to variable loads: Endurance limit, Size factor, Surface finish factor and Notch sensitivity. 9. What is difference between endurance strength and endurance limit of a material? 10. What is meant by stress concentration? How do you take it into consideration in case of a component subjected to dynamic loading? 11. How can stress concentration in a component be reduced? 12. Explain how the factor of safety is determined under steady and varying loading by different methods. 13. Write Soderberg s equation and state its application to different type of loadings. What information do you obtain from Soderberg diagram? 14. A flat plate is subjected to a tensile force of 5kN. The plate material is grey cast iron FG 200 and factor of safety is 2.5. Take stress concentration factor (K t ) for fillet section as 1.8 and that for hole section as Find the thickness of plate. 15. A machine component is subjected to a flexural stress which fluctuates between MN/m2 and 150 MN/m2. Determine the value of minimum ultimate strength according to (a) Gerber relation (b) Modified Goodman relation (c) Soderberg relation. Take yield strength = 0.55 Ultimate strength, Endurance strength = 0.5 Ultimate strength and factor of safety = A bar of circular cross-section is subjected to alternating tensile forces varying from a minimum of 200 kn to a maximum of 500 kn. It is to be manufactured of a material with an ultimate tensile strength of 900 MPa and an endurance limit of 700 MPa. Determine the diameter of bar using safety factors of 3.5 related to ultimate tensile strength and 4 related to endurance limit and a stress concentration factor of 1.65 for fatigue load. Use Goodman straight line as basis for design. 17. A steel rod is subjected to a reversed axial load of 180 kn. Find the diameter of the rod for a factor of safety of 2. Neglect column action. The material has an ultimate tensile strength of 1070 MPa and yield strength of 910 MPa. The endurance limit in reversed bending may be assumed to be one-half of the ultimate tensile strength. Other correction factors may be taken as follows: For axial loading = 0.7; for machined surface = 0.8; for size = 0.85; for stress concentration (K f ) = 1.0. Tutorial Sheet 2 1. Find the efficiency of the following riveted joints : Single riveted lap joint of 6 mm plates with 20 mm diameter rivets having a pitch of 50 mm. Double riveted lap joint of 6 mm plates with 20 mm diameter rivets having a pitch of 65 mm.

29 Assume, Permissible tensile stress in plate = 120 MPa, Permissible shearing stress in rivets = 90 MPa and Permissible crushing stress in rivets = 180 MPa. 2. A double riveted double cover butt joint in plates 20 mm thick is made with 25 mm diameter rivets at 100 mm pitch. The permissible stresses are: σ t = 120 MPa, τ = 100 MPa, σ c = 150 MPa. Find the efficiency of joint, taking the strength of the rivet in double shear as twice than that of single shear. 3. A double riveted lap joint with zig-zag riveting is to be designed for 13 mm thick plates. Assume σ t = 80 MPa, τ = 60 MPa and σ c = 120 MPa. State how the joint will fail and find the efficiency of the joint. 4. Two plates of 7 mm thick are connected by a triple riveted lap joint of zig-zag pattern. Calculate the rivet diameter, rivet pitch and distance between rows of rivets for the joint. Also state the mode of failure of the joint. The safe working stresses are as follows: σ t = 90 MPa, τ = 60 MPa and σ c = 120 MPa. 5. Design a double riveted butt joint with two cover plates for the longitudinal seam of a boiler shell 1.5 m in diameter subjected to a steam pressure of 0.95 N/mm 2. Assume joint efficiency as 75%, allowable tensile stress in the plate 90 MPa, compressive stress 140 MPa and shear stress in the rivet 56 MPa. 6. Design the longitudinal joint for a 1.25 m diameter steam boiler to carry a steam pressure of 2.5 N/mm 2. The ultimate strength of the boiler plate may be assumed as 420 MPa, crushing strength as 650 MPa and shear strength as 300 MPa. Take the joint efficiency as 80%. Sketch the joint with all the dimensions. Adopt the suitable factor of safety. 7. A steam boiler is to be designed for a working pressure of 2.5 N/mm 2 with its inside diameter 1.6 m. Give the design calculations for the longitudinal and circumferential joints for the following working stresses for steel plates and rivets : In tension = 75 MPa, In shear = 60 MPa and In crushing = 125 MPa. Draw the joints to a suitable scale. 8. Two lengths of mild steel tie rod having width 200 mm and thickness 12.5 mm are to be connected by means of a butt joint with double cover plates. Design the joint if the permissible stresses are 80 MPa in tension, 65 MPa in shear and 160 MPa in crushing. Make a sketch of the joint. 9. An eccentrically loaded lap riveted joint is to be designed for a steel bracket as shown in the figure. The bracket plate is 25 mm thick. All rivets are to be of the same size. Load on the bracket, P = 50 kn, rivet spacing C = 100 mm, load arm e = 400 mm. Permissible shear stress is 65 MPa and crushing stress is 120 MPa. Determine the size of the rivets to be used for the joint. Tutorial Sheet 3 1. A plate 100 mm wide and 12.5 mm thick is to be welded to another plate by means of parallel fillet welds. The plates are subjected to a load of 50 kn. Find the length of the weld so that the maximum stress does not exceed 56 MPa. Consider the joint first under static loading and then under fatigue loading. 2. A plate 75 mm wide and 12.5 mm thick is joined with another plate by a single transverse weld and a double parallel fillet weld as shown in the figure. The maximum tensile and shear stresses are 70 MPa

30 and 56 MPa respectively. Find the length of each parallel fillet weld, if the joint is subjected to both static and fatigue loading. 3. Determine the length of the weld run for a plate of size 120 mm wide and 15 mm thick to be welded to another plate by means of (a) A single transverse weld. (b) Double parallel fillet welds when the joint is subjected to variable loads. 4. A mm angle is to be welded to a steel plate by fillet welds as shown in the figure. If the angle is subjected to a static load of 200 kn, find the length of weld at the top and bottom. The allowable shear stress for static loading may be taken as 75 MPa. 5. A welded joint as shown in the figure. is subjected to an eccentric load of 2 kn. Find the size of weld, if the maximum shear stress in the weld is 25 MPa. Tutorial Sheet 4 i. The cylinder head of a steam engine is subjected to a steam pressure of 0.7 N/mm 2. It is held in position by means of 12 bolts. A soft copper gasket is used to make the joint leak-proof. The effective diameter of cylinder is 300 mm. Find the size of the bolts so that the stress in the bolts is not to exceed 100 MPa. ii. A steam engine of effective diameter 300 mm is subjected to a steam pressure of 1.5 N/mm 2. The cylinder head is connected by 8 bolts having yield point 330 MPa and endurance limit at 240 MPa. The bolts are tightened with an initial preload of 1.5 times the steam load. A soft copper gasket is used to make the joint leak-proof. Assuming a factor of safety 2, find the size of bolt required. The stiffness factor for copper gasket may be taken as 0.5.

31 iii. For supporting the travelling crane in a workshop, the brackets are fixed on steel columns as shown in the figure. The maximum load that comes on the bracket is 12 kn acting vertically at a distance of 400 mm from the face of the column. The vertical face of the bracket is secured to a column by four bolts, in two rows (two in each row) at a distance of 50 mm from the lower edge of the bracket. Determine the size of the bolts if the permissible value of the tensile stress for the bolt material is 84 MPa. Also find the cross-section of the arm of the bracket which is rectangular. iv. Design and draw a cotter joint (socket and spigot) to support a load varying from 30 kn in compression to 30 kn in tension. The material used is carbon steel for which the following allowable stresses may be used. The load is applied statically. Tensile stress = compressive stress = 50 MPa, shear stress = 35 MPa and crushing stress = 90 MPa. v. Design a sleeve and cotter joint to resist a tensile load of 60 kn. All parts of the joint are made of the same material with the following allowable stresses: σ t = 60 MPa, τ = 70 MPa and σ c = 125 MPa. vi. Design a knuckle joint to transmit 150 kn. The design stresses may be taken as 75 MPa in tension, 60 MPa in shear and 150 MPa in compression. vii. Design a knuckle joint for a tie rod of a circular section to sustain a maximum pull of 70 kn. The ultimate strength of the material of the rod against tearing is 420 MPa. The ultimate tensile and shearing strength of the pin material are 510 MPa and 396 MPa respectively. Determine the tie rod section and pin section. Take factor of safety = 6. viii. Design the rectangular key for a shaft of 50 mm diameter. The shearing and crushing stresses for the key material are 42 MPa and 70 MPa. ix. A 45 mm diameter shaft is made of steel with yield strength of 400 MPa. A parallel key of size 14 mm wide and 9 mm thick made of steel with yield strength of 340 MPa is to be used. Find the required length of key, if the shaft is loaded to transmit the maximum permissible torque. Use maximum shear stress theory and assume a factor of safety of 2. Tutorial Sheet 5 1. Find the diameter of a solid steel shaft to transmit 20 kw at 200 r.p.m. The ultimate shear stress for the steel may be taken as 360 MPa and a factor of safety as 8. If a hollow shaft is to be used in place of the solid shaft, find the inside and outside diameter when the ratio of inside to outside diameters is A solid circular shaft is subjected to a bending moment of 3000 N-m and a torque of N-m. The shaft is made of 45 C 8 steel having ultimate tensile stress of 700 MPa and a ultimate shear stress of 500 MPa. Assuming a factor of safety as 6, determine the diameter of the shaft. 3. A shaft supported at the ends in ball bearings carries a straight tooth spur gear at its mid span and is to transmit 7.5 kw at 300 r.p.m. The pitch circle diameter of the gear is 150 mm. The distances between the centre line of bearings and gear are 100 mm each. If the shaft is made of steel and the allowable shear stress is 45 MPa, determine the diameter of the shaft. Show in a sketch how the gear will be mounted on the shaft; also indicate the ends where the bearings will be mounted? The pressure angle of the gear may be taken as A hollow shaft is subjected to a maximum torque of 1.5 kn-m and a maximum bending moment of 3 kn-m. It is subjected, at the same time, to an axial load of 10 kn. Assume that the load is applied

32 gradually and the ratio of the inner diameter to the outer diameter is 0.5. If the outer diameter of the shaft is 80 mm, find the shear stress induced in the shaft. Tutorial Sheet 6 1. A cranked lever, as shown in the figure has the following dimensions : Length of the handle = 300 mm, Length of the lever arm = 400 mm & Overhang of the journal = 100 mm. If the lever is operated by a single person exerting a maximum force of 400 N at a distance of 1/3rd length of the handle from its free end, find : (a) Diameter of the handle, (b) Cross-section of the lever arm, and (c) Diameter of the journal. The permissible bending stress for the lever material may be taken as 50 MPa and shear stress for shaft material as 40 MPa. 2. A lever loaded safety valve is 70 mm in diameter and is to be designed for a boiler to blow-off at pressure of 1 N/mm2 gauge. Design a suitable mild steel lever of rectangular cross-section using the following permissible stresses: Tensile stress = 70 MPa, Shear stress = 50 MPa and Bearing pressure intensity = 25 N/mm 2. The pin is also made of mild steel. The distance from the fulcrum to the weight of the lever is 880 mm and the distance between the fulcrum and pin connecting the valve spindle links to the lever is 80 mm. 3. Design a right angled bell crank lever. The horizontal arm is 500 mm long and a load of 4.5 kn acts vertically downward through a pin in the forked end of this arm. At the end of the 150 mm long arm which is perpendicular to the 500 mm long arm, a force P act at right angles to the axis of 150 mm arm through a pin into a forked end. The lever consists of forged steel material and a pin at the fulcrum. Take the following data for both the pins and lever material: Safe stress in tension = 75 MPa, Safe stress in shear = 60 MPa and Safe bearing pressure on pins = 10 N/mm A foot lever is 1 m from the centre of shaft to the point of application of 800 N load. Find : (a) Diameter of the shaft (b) Dimensions of the key and (c) Dimensions of rectangular arm of the foot lever at 60 mm from the centre of shaft assuming width of the arm as 3 times thickness. The allowable tensile stress may be taken as 73 MPa and allowable shear stress as 70 MPa.

33 Tutorial Sheet 7 1. Design and make a neat dimensioned sketch of a muff coupling which is used to connect two steel shafts transmitting 40 kw at 350 r.p.m. The material for the shafts and key is plain carbon steel for which allowable shear and crushing stresses may be taken as 40 MPa and 80 MPa respectively. The material for the muff is cast iron for which the allowable shear stress may be assumed as 15 MPa. 2. Design a cast iron protective type flange coupling to transmit 15 kw at 900 r.p.m. from an electric motor to a compressor. The service factor may be assumed as The following permissible stresses may be used : Shear stress for shaft, bolt and key material = 40 MPa, Crushing stress for bolt and key = 80 MPa and Shear stress for cast iron = 8 MPa. Draw a neat sketch of the coupling. 3. Design and draw a protective type of cast iron flange coupling for a steel shaft transmitting 15 kw at 200 r.p.m. and having an allowable shear stress of 40 MPa. The working stress in the bolts should not exceed 30 MPa. Assume that the same material is used for shaft and key and that the crushing stress is twice the value of its shear stress. The maximum torque is 25% greater than the full load torque. The shear stress for cast iron is 14 MPa. 4. Design and draw a cast iron flange coupling for a mild steel shaft transmitting 90 kw at 250 r.p.m. The allowable shear stress in the shaft is 40 MPa and the angle of twist is not to exceed 1 in a length of 20 diameters. The allowable shear stress in the coupling bolts is 30 MPa. 5. Design a bushed-pin type of flexible coupling to connect a pump shaft to a motor shaft transmitting 32 kw at 960 r.p.m. The overall torque is 20 percent more than mean torque. The material properties are as follows : (a) The allowable shear and crushing stress for shaft and key material is 40 MPa and 80 MPa respectively. (b) The allowable shear stress for cast iron is 15 MPa. (c) The allowable bearing pressure for rubber bush is 0.8 N/mm 2. (d) The material of the pin is same as that of shaft and key. Draw neat sketch of the coupling. Tutorial Sheet 8 1. A flanged pipe with internal diameter as 200 mm is subjected to a fluid pressure of 0.35 N/mm 2. The elevation of the flange is shown in the figure. The flange is connected by means of eight M 16 bolts. The pitch circle diameter of the bolts is 290 mm. If the thickness of the flange is 20 mm, find the working stress in the flange.