Experiment is explained by the diagram and technical properties are given below the table. REFRIGERATION INSTRUCTION SET. t 2 compressor.

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1 EXPERIMENT 1 REFRIGERATION Cooling is transfering heat from lower heat source to a higher heat source. This kind of heat transfer doesn t occur naturally so cooling devices consume energy. Cooling is generally performed by vapor compression refrigeration cycle. Experiment is explained by the diagram and technical properties are given below the table. REFRIGERATION INSTRUCTION SET LP HP LP evaporator 1 6 t evaporator Capillary Tube 5 4 t 5 çek- 9 Hot gas defrost t 1 3 liquid compressor 2 1 Filter-dryer t 2 compressor t 3 1

2 TECHNICAL PROPERTIES 1 Compressor type and horse power LG 1/3 HP 2 Condenser capacity Fan&lamelled 3 Condenser fan capacity Fanco-42 W, 250 mm 4 Evaporator type Specific production,lameled 5 Evaporator fan 12x12 cm Tidar DP201-A 6 Inner balancing expansion valve Alco-TIE MW55-PCN Outer balancing expansion valve Alco-TIE MW55-PCN Capillary valve length 500 mm 9 Suction line valve Castel, 3/8 10 Liquid line valve Castel, ¼ 11 Pressure key Danhou, HLP 830 E 2

3 PURPOSE To calculate the coefficient of performance (COP) of the refrigeration system, the isentropic efficiency of the compressor and the second law efficiencies of the equipments. INSTRUCTION OF EXPERIMENT 1) Turn on 1, 2, 4 numbered valves and turn off other valves. 2) Operate both of the compressors, condenser and second evaporator s fan by the help of control board. 3) When the system become steady state record measurements from the control board. Properties/ Measurement No Indicator 1 1) Compression line pres., p 2 (kpa) HP 2) Condenser temperature t y ( 0 C) HP 3) Evaporator pressure, p e1 (kpa) LP1 4) Evaporation temperature, t e1 ( 0 C) LP1 5) Evaporator exit temp, t eç1 ( 0 C) t 1 6) Superheating value, (t eç1 -t e1 ) ( 0 K) - REPORT AND OBSERVATIONS a) Show the actual cycle with saturation line on P-h diagram. b) Calculate the compressor exit temperature for η=100% c) Calculate the isentropic efficiency of the compressor for the recorded exit temperature of the compressor (η=?) d) Calculate the compressor work and the cooling load per unit mass. e) Calculate the COP f) Calculate the second law efficiency of the compressor and the evaporator. 3

4 EXPERIMENT 2 DUCT TYPE FANNED AIR HEATER Purpose By making related measurements at duct type fanned air heater defining energy interaction types between systems and calculating amounts of them. Understanding thermodynamics 1 and Heat Transfer principles. Basic Knowledge To define types of energy interaction between systems and to calculate amounts of them fundamentals of Thermodynamics 1 and heat transfer has to be recalled. Duct type fanned air heater is similar to a basic hair dryer and while measurement is done it may be assumed as steady flow machine because air flows steadily at constant temperature and constant mass flow and air is heated over electrical resistance wires. That is why thermodynamic analysis may be done by using steady flow open system model. Electrical energy that resistance wires take turns into thermal energy and considerable part of the thermal energy is transfered by convection to air that flows over the wires and the rest of the energy is transfered to duct surface by radiation over wires and by convection on heated air, then heat transfer by convection over the duct surface to surroundings occurs. For calculation mass flow is needed. Mass flow will be calculated as learned at fluid mechanics lessons from maximum speed, average speed contexts. Experiment Duct type fanned air heater s duct is made of black sheet material called Stainless steel sheet with 1 mm thickness, 1 m long with a rectangular cross sectional area 0.42x0.16 m. At one end of the duct there is a constant revolution centrifuge fan which works with 24 DC by spinning provides air from ambient to the duct. At the bottom of the duct there are 3 resistance wires which are used at quartz furnaces. Total resistance power may be set for 3 degrees. At standard operation conditions one of the wires consume 537 W, two of them consume 1033 W and three of them consume 1483 W of power. Air temperature is measured before and after flowing through the duct by digital thermometers adapted to 2 different thermocouples. At the center of the cross sectional area speed of the air is measured as 1,6 m/s. Outer surface of the duct is isolated by carbon saturated isolated glass material where surface temperature is relatively higher for reducing heat losses. After setting resistance power plug in device is operated and after air temperature staying constant they are read by digital thermometers. These values are enough for the calculations. Report and Observations a) Calculate the amount of heat that transferred to the air from the resistance b) Calculate the thermal efficiency of the electrical resistance c) Calculate the Reynolds number d) Calculate the heat transfer coefficient e) Assuming that there is constant heat flux calculate the the exit temperature of the air using correlations and compare the result with the obtained value during the experiment. 4

5 humidifier EXPERIMENT 3 HEAT RECOVERY and HEAT EXCHANGER Fundamentals of Heat Recovery To choose the right device for the heat recovery, it is needed to calculate exact heating load correctly Basic elements for the heat recovery unit are listed below; 1. Temperature 2. Air Movements (circulation) 3. Ventilation (Clean air input) HEAT RECOVERY EDUCATION SET SCHEME exhaust t5 t3 Heat exchanger t11 t6 t4 t12 Pre heater Exhaust damper cooler t7 t9 t1 radiator fan t8 t10 t2 inner climate Fresh air ent. 5

6 Electric Control Scheme R A A-meter Dimmer (velocity control) V V A V-meter M M M Mp Fan Motor Compressor Condensor Preheater Finalheater V-feeder A-feeder TECHNICAL PROPERTIES 1 Fan brand and model 2 Fan motor power and rpm 45 W, 1350 rpm 3 Fan capacity 850 m 3 /h 4 Preheater power 1055 W 5 Finalheater power 1055 W 6 Humidifier type Water injection type 7 Heatexchanger Type and Material Aluminum plates 8 Heatexchanger Model BT AL 03 N 021 M T AZ SC 9 Dimensions of Heatexchanger 300x300x Heat exchanger series number and width 27 series-7,5 mm 11 Damper dimensions 200x230 mm 6

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8 EXPERIMENT Calculation the Thermal Efficiency of the Heat Recovery System 1. PURPOSE Getting knowledge about plated heat recovery unit and calculating the thermal efficiency. 2. NEEDED DEVICES AND MATERIALS Air speed meter (anemometer) 3. INSTRUCTION OF EXPERIMENT a) Switch on the fuse and make fan and heaters work. b) Record the required temperatures of the system from the control board. 4. REPORT AND CONCLUSIONS Measurement Number 1 Inlet dry thermometer, t 1 [ 0 C] Inlet wet thermometer t 2 [ 0 C] Heat exchanger exhaust dry thermometer, t 3 [ 0 C] Heat exchanger exhaust wet thermometer t 4 [ 0 C] Final cooler exhaust wet therm., t 9 [ 0 C] Final cooler exhaust dry therm., t 10 [ 0 C] Heat exchanger exhaust dry therm., t 11 [ 0 C] Heat exchanger exhaust wet therm., t 12 [ 0 C] Rate of air, u [m/s] Specific volume of air,[m 3 /kg] a)show the cycle on physcometric chart. b)calculate the thermal efficiency of the heat exchanger t 3 t11 η =(t 3 -t 1 )/(t 9 -t 1 ) t 9 t 1 8