EN M '
|
|
- Abigayle Welch
- 7 years ago
- Views:
Transcription
1 THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS 345 E. 47th St New York, N.Y The Society shall not be responsible for statements or opinions advancedin papers or &Scission at meetings of the Society or of its Divisions or Sections, or printed in its publications. Discussion is printed only if the paper is published in an ASME Journal. Authorization to photocopy material for internal. or personal use under circumstance not falling within the fair use provisioneof the Copyright Act is granted by ASME to libraries and other users registered with the Copyright Clearance Center (CCC) Transactional Reporting Service provided that the base fee of $0.30 per page Is paid directly to the CCC, 27 Congress Street Salem MA Requests for spaal permiszicii or bulk reproduction shottkl be addressed to the ASME Technical Publishing Department Copyright by ASME All Flights Reserved. Printed in U.S.A "FLUID TRANSIENT RESPONSES WITH CHECK VALVES IN PIPE FLOW SYSTEM WITH AIR ENTRAINMENT" EN M ' BREAK T.S.Lee and L.C.Leow Mechanical and Production Engineering Department National University of Singapore SINGAPORE ABSTRACT A common flow system arrangement in piping system consists of a lower reservoir, a group of pumps with a check valve in each branch, and a pipeline discharging into a upper reservoir. In earlier studies of check valves performances in transient flow, none considered the effects of air entrainment into a pipeline system and the subsequent effects on the. check valve performances in transient flow. Studies on pressure surges during pump tripped in pumping systems showed that by including an air entrainment variable wave speed model, reasonable predictions of fluid transient responses with proper phasing and attenuation of pressure peaks can be obtained. The most severe case where all the pumps in the station fail simultaneously due to power failure was analysed for their maximum and minimum pressure variation along the pipeline. A numerical model is now set up in the present work to investigate the check valve performances in transient flow for a pumping system with air entrainment. The analyses examine a fluid system with a variable air entrainment content (c) and studied numerically it effects on the flow reversal time and hence determine the appropriate valve selection for a given fluid system to minimize problems of check valve slamming. Present numerical computations show that the air content in a fluid system can adversely affect the check valve transient responses. With the fluid system operating within a critical range of air entrainment values, analysis showed that there is a possibility of "check valve slamming" when the check valves were selected based on the analysis of an air free system. The above phenomena is confirmed through physical field measurements. Presented at the ABE ASIA '97 Congress dt Exhibition Singapore - September 30-October 2,1997
2 1. INTRODUCTION A common flow system arrangement in fluid engineering consists of a lower reservoir, a group of pumps with a check valve in each branch, and a pipeline discharging into an upper reservoir. In earlier studies of check valve performances in transient flow Wrovoost( ), Thorley( )J, none considered the effects of air entrainment into a pipeline system and the subsequent effects on the check valve performances. A pipeline contour of a pumping station with possible air entrainment is shown in Figure 1. This profile was also chosen among some other previous studies due to its known check valve slamming characteristics. Possible air entrainment into this pumping station was also due to its frequent operation near low cut-out water levels in the sump [Lee (1991, 1994)]. The most severe case of all the pumps in the station fail simultaneously due to power failure was analysed for their maximum and minimum pressure variation along the pipeline. A numerical model was set up in the present work to investigate the check valve performances in a pumping system with air entrainment. The present analysis examines a fluid system with an air entrainment content (c). Nuumerical studies show that effects on the flow reversal time, and hence, the appropriate valve selection for a given fluid system to minimize the problem of check valve slamming. From the study by Thorley(1989), it is observed that the rate of decrease for a given flow rate is approximately linear over the interval when the flow rate starts to decrease and eventually reverses. This physical observation is implemented in the present numerical calculation procedures in order to better determine the suitability of a check valve type for a given pumping system. 2. METHOD OF CHARACTERISTICS WITH VARIABLE WAVE SPEED The method of characteristics applied to the above pressure tfansient problem with variable wave speed (ai), can be described by the C and C characteristics lines: C + characteristics g H) (V1" 1 - V) g fi + a At k At k a i 2D R V IV I = 0 R R X -x At k - v +a R R 2
3 and C - characteristics g ) (V /" 1 -V s ) g fl s s 1 V s sin a + V IV 1 = 0 s s a s At " At " a 2D X -x at " - V s -a s With air entrainment, the transient computation of the fraction of air content (CI ) along the pipeline depends on the local pressure and local air volume and is given in [Lee(1994)]. The loss factor fl used in conjunction with the Method of Characteristics with air entrainment and gas released in a pipeline system is evaluated at the local point (i) using the characteristics of the flow at that point. The steady state overall loss factor at the operating point of a system can be determined from the pump characteristic curve and the system curve [Lee(1991)]. 3. NUMERICAL COMPUTATION OF PUMPS RUN DOWN WITH DYNAMIC CHECK VALVE RESPONSES Downstream of the pipeline profile [Figure 11 of the pumping station, a constant head reservoir is assumed for all time level. The upstream pumping station is modelled by an equivalent pump characteristics with number of pumps (np) running in parallel. During pumps stoppage and pumps run down, the homologous relationship for np number of pumps in the form of an equivalent pump is numerically modelled [Lee[1994]. When the reversed flow is encountered in the pump, the check valve response is modelled here according to the experimental data obtained by Thorley(1989) on the dynamic characteristics of the check valves: Vx/ Vo = Di + D2 (A * ) + D3 (A * ) + D4(A* ) 3 where A s = reverse flow deceleration parameter through the check valve = IdV/dt1/ [ (V0) 2/ D] Vo = steady state flow velocity dv/dt = reverse flow velocity gradient D = check valve nominal diameter Di, D2, D3 are the characteristic parameters of the type of check valve Da is the characteristic parameter of the check valve due the effects of the air entrainment. For no air entrainment, 1)4 = 0.0. Check valves serve to prevent the reversal of the flow in a pumping system. If however, the reversal of the flow occurs in a very short time the valve may close when the flow already has been reversed. Depending on the type of check valve used, a sudden decrease of the reversal flow will 3
4 occur, resulting in undesirable pressure variations and slamming of the valve. Thorley(1989) gave some very good examples of check valve slamming in pumping systems. To theoretically predict whether slamming of a check valve is to be expected, data under dynamic conditions of the valve must be known. In most cases these data are not known. However, the possibility of a check valve slamming may be estimated through a numerically predicted "flow reversal time (tr)". Prototype valve tests showed that the fluid velocity gradient IdV/dt1 variation with time is of decisive importance when considering the valve slam problem. Obviously, the shorter the time for transient flow reversal from pump trip, the more likely that valve slamming will occur. This again depends on the type of check valve used. Nozzle type of recoil check valves tend to have a better dynamic response than the conventional swing type check valve. It is thus important to know the "flow reversal time" during pump trip so that at the design stage, it is possible to predict whether the chosen type of check valve will satisfy the design specifications of the pumping system. Specifically, the aim of this study is to determine the air entrainment effects on the "flow reversal time" and its effects on the check valve selection and the consequences of pressure surges for a pumping system. 4. RESULTS AND DISCUSSIONS Initially, the effects of air entrainment on pressure transients generated by the simultaneous pump trip of all pumps operating in a pumping station with the undulating pipeline contour as shown in Figure 1 were investigated for a selected swing check valve configuration. The pumping station uses three parallel centrifugal pumps to supply 1.08 m Is of water to a tank 19.7 m above the sump level, through a m diameter main of 4720 m length. Swing check valves were installed downstream of the pumping station. The pumpset moment of inertia (including the flywheel) were studied for an equivalent pumpset moment of inertia of Ie = 0.1, 0.1, 1.0, 2.0, 5.0 and 10 of a reference pumpset inertia (I) of 99.9 kg-m. The air void fraction (c) studied were in the range of 0.00 to Figure 2 shows the effects of air entrainment on the pressure transients at a point A (immediate downstream of the check valves) and at a point B (at the peak) of the pipeline contour for an equivalent pumpset moment of inertia (Ie). Several distinct pressure transient characteristics were observed from the above numerical experiments: (i) The magnitude of the maximum pressure surges varies with c and is very often larger than that predicted by the constant wave speed model (c=0.000) (ii) The damping of surge pressure is noticeably larger with when compared with the constant wave speed model (c=0.000) (iii) With , the pressure surges are asymmetric with respect to the static head, while the pressure transients for the constant wave speed model were symmetric with respect to the static head. (iv) When air was entrained into the system, the pressure transient showed long periods of downsurge and short periods of upsurge when compared with the gas-free constant wave speed case. From past experiences, surge measurements (Lee(1994)) indicate that the damping is faster in the actual system indicating that more energy dissipating mechanisms than ordinary friction are at hand. (v) The degree 4
5 of amplification of the first pressure peak is dependent upon the rate of deceleration of the flow after the pump trip. An increased pump inertia (by attaching a flywheel to the drive-shaft) generally produces a slower rate of deceleration of the flow after pump trip and a smaller amplification of the first pressure peak as compared with the constant wave speed model. Figure 3 showed that the entrained, entrapped or released gases significantly altered the flow reversal time. From the available flow' reversal time, the reverse flow velocity gradient with respect to time is obtained. The maximum reverse flow gradient and the corresponding maximum reverse flow for a given pumping configuration at various air entrainment levels for a swing check valve is shown in Figure 4. The results show that although the selection of the swing check valve is in general satisfactory for the above pumping system, there is still a possibility of the "valve slamming" problem unless the pumpset inertia is significantly increased. The results presented in Figure 3 show that the effects of the check valves in transient flow can be predicted by means of numerical computation of the equivalent flow reversal time. When analysing these effects, both steady flow rate and fluid velocity gradient with time must be considered. For systems with large flow rates ' the fluid velocity gradient is of decisive importance. The time interval necessary for flow reversal and mode of the flow rates versus time variation during the flow reversal period gives an indication of the necessary characteristics for a satisfactory flow and pressure prediction of the check valve closure. The above observations made through numerical experiments are consistent with field measurements and observations (Lee(1994)) of pressure surges in prototype pumping stations at various mode of pump normal operations and pumps operating near low water cut-out levels with air entrainment due to attached surface vortex. Observations showed that the commonly used swing check valve closed when flow reversed. At the instant of valve closure, a large pressure variation was initiated. S. CONCLUSIONS The present analysis show that the effects of air entrainment on the check valve performances in transient flow with various mode of pumps operations may be predicted by means of a numerical computation of the equivalent flow reversal time. Both steady flow rate and fluid velocity gradient with time need to be considered in the computation. The time. interval needed for flow reversal, and mode of the flow rates versus time variation during the flow reversal period, gives an indication of the required check valve characteristics necessary for a satisfactory pressure transient in a pumping system without valve slamming problem. From the analysis, it is seen that in order to find the most severe conditions of pressure surges and valve slamming for a given fluid system, it is necessary to perform a complete air entrainment computional study. The reason is that for a given system, the maximum pressure peaks and valve slamming phenomena may not always occur at the minimum or maximum air entrainment levels, and can occur within a range of intermediate air entrainment values. This range of critical air entrainment values can only be obtained through numerical 5
6 experimentation. Physical experiments with a model setup for air entrainment investigation are not reliable [Lee and Pejovic (1996)1. 6. ACKNOWLEDGEMENTS The author gratefully acknowledges the kind assistance of the personnel from the Ministry of the Environment, Singapore for providing valuable information on pumping stations for this investigation. The support of the National University of Singapore Research Grant ( No. RP ) is also gratefully acknowledged. 7. REFERENCES Lee, T.S., "Numerical computation of fluid pressure transients in pumping installations with air entrainment", Int. J. for Numerical Methods in Fluids, Vol.12, pp (1991). Lee, T.S., "Numerical Modelling and Computation of Fluid Pressure Transients with Air Entrainment in Pumping Installations", Int. J. for Numerical Methods in Fluids", Vol.18, pp (1994). Lee, T.S. and Pejovic, S., "Air Influence on Similarity of Hydraulic Transients and Vibrations", ASME Journal of Fluids Engineering, Vol.118, December pp Provoost, G.A., "The Dynamic behaviour of Non-Return Valves", Proceedings of the Third International Conference on Pressure Surges, Canterbury, England, March 24-27, pp Provoost, G.A., "The Dynamics Characteristics of Non-Return Valves", Paper 14, 11th IAEA Symposium of the Section on Hydraulic Machinery, Equipment and Cavitation Operational Problems of Pump Stations and Power Plants, Amsterdam, Sept Provoost, G.A., "A Critical Analysis to Determine the Dynamic Characteristics of Non-Return Valves", Paper F4, Proceedings 4th Int. Conf. on Pressure Surges, BHRA, Bath, Sept. 1983, pp Thorley, A.R.D., "Dynamic Response of Check Valves", Paper fl, Proceedings of 4th Int. Conf. on Pressure Surges, BHRA, Bath, Sept. 1983, pp Thorley, A.R.D., "Check Valve Behavior Under Transient Flow Conditions : A State-of-the-Art Review", ASME Journal of Fluid Engineering, June 1989, Vol.111, pp
7 PIPELINE CONTOUR ELEVATION (METERS ) ttl A CHAINAGE (METERS) FIGURE 1. A TYPICAL PIPELINE CONTOUR OF PUMPING STATION WITH POSSIBLE AIR ENTRAINMENT
8 (a) c = (b) c = = ID 1 14 SO 1111 lir& I. SCROK5 *._./..., 0.0 LZ CAI GO.L C.0 =A MA MA MO MA 71z: In SCCONCI5 (c) c = (d) c = a I\ /r/....k 0.7 al 41 WA WO 4111 MO MA 1111 M.: TRR N SECON25 S..,. R \ ( n:.o U, MI MI M., 1:1 Mt MA. e TIC in SCC0.75 (e) c = S Cl) c = _ F 0.0 AA OA CO Ma MA la a.r.. it- TM: IN SECOROS R 71./ N SECCRO5 FIGURE 2. AIR ENTRAINMENT EFFECTS ON TRANSIENT PRESSURE HEADS DOWNSTREAM OF PUMPING STATION AT A ( ) PEAK OF PIPELINE ELEVATION AT B ( ): (i) c=0.000 (ii) c=0.001 (iii) c=0.005 (iv) c=0.010 (v) c=0.020 (vi) c=0.030
9 EOLINALD1T PUMPSCI IMETITIA.34 I I. 0.5 I Agaj 40 i I I if. 5.0 e li AIR ENTRAINMENT (c) FIGURE 3. EFFECTS OF AIR CONTENT c ON FLOW REVERSAL TIME
10 2.0 (i) It = If CC (iii) Ie = 101 I 0 SWING ON 100 (ii) IC = 1.01 SPLIT DISK (w) ON /' SPLIT DISK (s) ON >,---- NOZZLE (s) DN i..., DECELERATION PARAMETER, A= ICW/dt1/1(W0) 2 /pi FIGURE 4. EFFECTS OF AIR CONTENT c ON SELECTION OF CHECK VALVES (1) Ie = 0.11 (ii) Ie = 1.01 (iii) Ie = 101
check valve slam A methodology for predicting
BY JOHN V. BALLUN A methodology for predicting check valve slam USING A METHODOLOGY DEVELOPED BY EXTENSIVE TESTING, DESIGNERS CAN MATCH THE DYNAMICS OF A PUMPING SYSTEM WITH THE NONSLAMMING CHARACTERISTICS
More informationWater hammering in fire fighting installation
Water hammering in fire fighting installation Forward One of major problems raised in the fire fighting network installed at Pioneer company for pharmaceutical industry /Sulaymania was the high water hammering
More informationBLADDER SURGE CONTROL SYSTEM
PART I GENERAL 1.01 Description BLADDER SURGE CONTROL SYSTEM This specification describes the requirements for a Bladder Surge Control System. The purpose of the system is to minimize transient pressures
More informationAPPENDIX A CONTROL VALVE TESTING PROCEDURES AND EQUATIONS FOR LIQUID FLOWS
APPENDIX A CONTROL VALVE TESTING PROCEDURES AND EQUATIONS FOR LIQUID FLOWS Section A.1. Flow Coefficients Definition The flow coefficient or pressure loss coefficient is used to relate the pressure loss
More informationMinor losses include head losses through/past hydrants, couplers, valves,
Lecture 10 Minor Losses & Pressure Requirements I. Minor Losses Minor (or fitting, or local ) hydraulic losses along pipes can often be estimated as a function of the velocity head of the water within
More informationpressure inside the valve just before the final release of air. in pipeline systems resulting from 2p 1 p a m C D A o
BY SRINIVASA LINGIREDDY, DON J. WOOD, AND NAFTALI ZLOZOWER It is a common practice to locate air valves at high elevations along water transmission mains. Improper sizing of an air valve could lead to
More informationHead Loss in Pipe Flow ME 123: Mechanical Engineering Laboratory II: Fluids
Head Loss in Pipe Flow ME 123: Mechanical Engineering Laboratory II: Fluids Dr. J. M. Meyers Dr. D. G. Fletcher Dr. Y. Dubief 1. Introduction Last lab you investigated flow loss in a pipe due to the roughness
More informationInvestigations of a Long-Distance 1000 MW Heat Transport System with APROS Simulation Software
th International Conference on Structural Mechanics in Reactor Technology (SMiRT ) Espoo, Finland, August 9-4, 9 SMiRT -Division 3, Paper 56 Investigations of a Long-Distance MW Heat Transport System with
More informationGuidelines for Transient Analysis in Water Transmission and Distribution Systems
Chapter 1 Guidelines for Transient Analysis in Water Transmission and Distribution Systems Ivo Pothof and Bryan Karney Additional information is available at the end of the chapter http://dx.doi.org/10.5772/53944
More informationPVP2007-26676 INTERPRETING SURGE ANALYSIS RESULTS
Proceedings of PVP27 27 ASME Pressure Vessels and Piping Division Conference July 22-26, 27, San Antonio, Texas, USA PVP27-26676 INTERPRETING SURGE ANALYSIS RESULTS McGuffie, S.M. Porter McGuffie, Inc.
More informationEXPERIMENTAL RESEARCH ON CHARACTERISTICS OF CENTRIFUGAL PUMP NOISE IN WATER PIPE SYS- TEM
The 21 st International Congress on Sound and Vibration 13-17 July, 2014, Beijing/China EXPERIMENTAL RESEARCH ON CHARACTERISTICS OF CENTRIFUGAL PUMP NOISE IN WATER PIPE SYS- TEM Muze Huang, Hongling Sun,
More informationPressure drop in pipes...
Pressure drop in pipes... PRESSURE DROP CALCULATIONS Pressure drop or head loss, occurs in all piping systems because of elevation changes, turbulence caused by abrupt changes in direction, and friction
More informationCOUNTERBALANCE VALVES
COUNTERBALANCE VALVES Introduction They are modulating valves which allow free flow into the actuator and then block the reverse flow until they feel a pilot pressure inversely proportional to the load
More informationL r = L m /L p. L r = L p /L m
NOTE: In the set of lectures 19/20 I defined the length ratio as L r = L m /L p The textbook by Finnermore & Franzini defines it as L r = L p /L m To avoid confusion let's keep the textbook definition,
More informationFLOW MEASUREMENT 2001 INTERNATIONAL CONFERENCE DERIVATION OF AN EXPANSIBILITY FACTOR FOR THE V-CONE METER
FLOW MEASUREMENT 200 INTERNATIONAL CONFERENCE DERIVATION OF AN EXPANSIBILITY FACTOR FOR THE V-CONE METER Dr D G Stewart, NEL Dr M Reader-Harris, NEL Dr R J W Peters, McCrometer Inc INTRODUCTION The V-Cone
More informationExperiment 3 Pipe Friction
EML 316L Experiment 3 Pipe Friction Laboratory Manual Mechanical and Materials Engineering Department College of Engineering FLORIDA INTERNATIONAL UNIVERSITY Nomenclature Symbol Description Unit A cross-sectional
More informationPumps: Convert mechanical energy (often developed from electrical source) into hydraulic energy (position, pressure and kinetic energy).
HYDRAULIC MACHINES Used to convert between hydraulic and mechanical energies. Pumps: Convert mechanical energy (often developed from electrical source) into hydraulic energy (position, pressure and kinetic
More informationPractice Problems on Pumps. Answer(s): Q 2 = 1850 gpm H 2 = 41.7 ft W = 24.1 hp. C. Wassgren, Purdue University Page 1 of 16 Last Updated: 2010 Oct 29
_02 A centrifugal with a 12 in. diameter impeller requires a power input of 60 hp when the flowrate is 3200 gpm against a 60 ft head. The impeller is changed to one with a 10 in. diameter. Determine the
More informationHydraulic Pipeline Application Modules PSI s Tools to Support Pipeline Operation
Hydraulic Pipeline Application Modules PSI s Tools to Support Pipeline Operation Inhalt 1 Leak Detection and Location Modules... 3 1.1 Dynamic Balance Leak Detection... 3 1.2 Transient Model Leak Detection...
More informationACOUSTICS IN PUMPING SYSTEMS
ACOUSTICS IN PUMPING SYSTEMS by Robert McKee Program Manager-R&D and Eugene Buddy Broerman Research Engineer Southwest Research Institute San Antonio, Texas Robert J. McKee is currently a Program Manager
More informationAir Eliminators and Combination Air Eliminators Strainers
Description Air Eliminators and Combination Air Eliminator Strainers are designed to provide separation, elimination and prevention of air in piping systems for a variety of installations and conditions.
More informationw o r k o G f E A x - p r S i t n c e Elegance and Strength BBR HiAm CONA Strand Stay Cable Damping Systems
e o b a l N e t w o r k l o G f E A x - p r S i t n c e 1 9 4 4 - s Elegance and Strength BBR HiAm CONA Strand Stay Cable Damping Systems 1 Cable vibration and damping Despite the wide use of cable-stayed
More information20 years of FSI experiments in Dundee
20 years of FSI experiments in Dundee Arris S Tijsseling a, Alan E Vardy b a Eindhoven University of Technology, Department of Mathematics and Computer Science, P.O. Box 513, 5600 MB Eindhoven, The Netherlands
More informationmeasurement, but almost any pipe elbow can be calibrated Elbow meters are not as potentially accurate as venturi,
Lecture 14 Flow Measurement in Pipes I. Elbow Meters An elbow in a pipe can be used as a flow measuring device much in the same way as a venturi or orifice plate The head differential across the elbow
More informationChapter 10. Flow Rate. Flow Rate. Flow Measurements. The velocity of the flow is described at any
Chapter 10 Flow Measurements Material from Theory and Design for Mechanical Measurements; Figliola, Third Edition Flow Rate Flow rate can be expressed in terms of volume flow rate (volume/time) or mass
More informationUsers Guide. By Dr. Don J. Wood Dr. Srinivasa Lingireddy. Featuring the Surge Wizard
Users Guide By Dr. Don J. Wood Dr. Srinivasa Lingireddy Featuring the Surge Wizard Copyrighted KYPIPE LLC 2010 1 EPASurge Users Guide Overview EPASurge is a powerful transient analysis program designed
More informationSelection Of Centrifugal Pumping Equipment 1
Circular 1048 Selection Of Centrifugal Pumping Equipment 1 Dorota Z. Haman, Fedro S. Zazueta, Forrest T. Izuno 2 INTRODUCTION The pump is an essential component of an irrigation system. Proper selection
More informationFLUID FLOW HYDRAULIC LIQUID SURGE (ENGINEERING DESIGN GUIDELINE)
Page : 1 of 62 Guidelines for Processing Plant www.klmtechgroup.com KLM Technology #03-12 Block Aronia, Jalan Sri Perkasa 2 Taman Tampoi Utama 81200 Johor Bahru (ENGINEERING DESIGN GUIDELINE) Co Author
More informationSurge Modeling Tips and Procedures Dr. Don J. Wood & Dr. Srinivasa Lingireddy
Surge Modeling Tips and Procedures Dr. Don J. Wood & Dr. Srinivasa Lingireddy This Document contains a collection of answers to often asked questions, tips and advice for surge modeling. As always please
More informationSELECTION OF TRANSIENT ANALYSIS SOFTWARE FOR PIPELINE DESIGN: TOWARDS A EUROPEAN STANDARD
SELECTION OF TRANSIENT ANALYSIS SOFTWARE FOR PIPELINE DESIGN: TOWARDS A EUROPEAN STANDARD PETER J. BAKER (1); HELENA RAMOS(2) (1) Marketing Engineer, FLOWMASTER International Limited, United Kingdom (2)
More informationC. starting positive displacement pumps with the discharge valve closed.
KNOWLEDGE: K1.04 [3.4/3.6] P78 The possibility of water hammer in a liquid system is minimized by... A. maintaining temperature above the saturation temperature. B. starting centrifugal pumps with the
More informationPULSATION REDUCTION BY ACOUSTIC FILTERS FOR METERING APPLICATIONS. Robert J. McKee Ray G. Durke
PULSATION REDUCTION BY ACOUSTIC FILTERS FOR METERING APPLICATIONS Robert J. McKee Ray G. Durke Southwest Research Institute 6220 Culebra Road San Antonio, TX 78238 INTRODUCTION Because of the adverse effects
More informationOPERATING FANS IN PARALLEL IN VIEW OF VARIABLE FLOW RATE OUTPUT
OPERATING FANS IN PARALLEL IN VIEW OF VARIABLE FLOW RATE OUTPUT Eddy J. Jacques & Pierre J. Wauters Department of Mechanical Engineering, Unité TERM, Université Catholique de Louvain, Belgium ABSTRACT
More informationDynamic Modeling Of An Ozone Disinfection Facility
Dynamic Modeling Of An Ozone Disinfection Facility Michael Etheridge Black & Veatch 8400 Ward Parkway Kansas City, MO 64114 Presented to the Fourteenth Ozone World Congress August 25 th, 1999 ABSTRACT
More informationCO 2 41.2 MPa (abs) 20 C
comp_02 A CO 2 cartridge is used to propel a small rocket cart. Compressed CO 2, stored at a pressure of 41.2 MPa (abs) and a temperature of 20 C, is expanded through a smoothly contoured converging nozzle
More informationLecture 24 Flumes & Channel Transitions. I. General Characteristics of Flumes. Flumes are often used:
Lecture 24 Flumes & Channel Transitions I. General Characteristics of Flumes Flumes are often used: 1. Along contours of steep slopes where minimal excavation is desired 2. On flat terrain where it is
More informationUse of OpenFoam in a CFD analysis of a finger type slug catcher. Dynaflow Conference 2011 January 13 2011, Rotterdam, the Netherlands
Use of OpenFoam in a CFD analysis of a finger type slug catcher Dynaflow Conference 2011 January 13 2011, Rotterdam, the Netherlands Agenda Project background Analytical analysis of two-phase flow regimes
More informationOpen Channel Flow. M. Siavashi. School of Mechanical Engineering Iran University of Science and Technology
M. Siavashi School of Mechanical Engineering Iran University of Science and Technology W ebpage: webpages.iust.ac.ir/msiavashi Email: msiavashi@iust.ac.ir Landline: +98 21 77240391 Fall 2013 Introduction
More informationChapter 3.5: Fans and Blowers
Part I: Objective type questions and answers Chapter 3.5: Fans and Blowers 1. The parameter used by ASME to define fans, blowers and compressors is a) Fan ration b) Specific ratio c) Blade ratio d) Twist
More informationUnderstanding Plastics Engineering Calculations
Natti S. Rao Nick R. Schott Understanding Plastics Engineering Calculations Hands-on Examples and Case Studies Sample Pages from Chapters 4 and 6 ISBNs 978--56990-509-8-56990-509-6 HANSER Hanser Publishers,
More informationPump Cavitation Physics, Prediction, Control, Troubleshooting
Pump Cavitation Physics, Prediction, Control, Troubleshooting Short Course Instructors: Bruno Schiavello & Frank Visser Short Course Pump Cavitation Physics, Prediction, Control, Troubleshooting Bruno
More informationTHE USE OF A CORIOLIS FLOW METER FOR MEASURING MOLASSES PRODUCTION IN A SUGAR MILL. ABSTRACT
THE USE OF A CORIOLIS FLOW METER FOR MEASURING MOLASSES PRODUCTION IN A SUGAR MILL. P. W. Rein 1, D. J. Muzzell 2, and N. Dolan 2 1 Audubon Sugar Institute, LSU AgCenter, St. Gabriel, LA, 2 Raceland Raw
More informationTD10. Selecting Circulators. Technical Documents. Taco Radiant Made Easy Application Guide STEP 1: ESTABLISH THE TARGET FLOW RATE FOR THE SYSTEM
EFFECTIVE:August, Taco Radiant Made Easy Application Guide Selecting Circulators Technical Documents TD SUPERSEDES: New This article shows you how to select a Taco circulator that lets the hydronic system
More informationChapter 13 OPEN-CHANNEL FLOW
Fluid Mechanics: Fundamentals and Applications, 2nd Edition Yunus A. Cengel, John M. Cimbala McGraw-Hill, 2010 Lecture slides by Mehmet Kanoglu Copyright The McGraw-Hill Companies, Inc. Permission required
More informationTOPIC: 191004 KNOWLEDGE: K1.01 [3.3/3.5] Which one of the following contains indications of cavitation in an operating centrifugal pump?
KNOWLEDGE: K1.01 [3.3/3.5] P21 Which one of the following contains indications of cavitation in an operating centrifugal pump? A. Low flow rate with low discharge pressure. B. Low flow rate with high discharge
More informationTheory, Application, and Sizing of Air Valves
Theory, Application, and Sizing of Air Valves VAL-MATIC VALVE AND MANUFACTURING CORP. 905 RIVERSIDE DRIVE, ELMHURST, IL 60126 TEL. (630) 941-7600 FAX. (630) 941-8042 www.valmatic.com 1 THEORY, APPLICATION,
More informationNozzle Check Valves. NOREVA nozzle check valves are used
Nozzle Check Valves NOREVA nozzle check valves are used in applications where the reverse flow of a fluid has to be avoided. These valves are suitable for all kind of liquid and gaseous fluids and fire
More informationRECYCLED MICRO HYDROPOWER GENERATION USING HYDRAULIC RAM PUMP (HYDRAM)
IMPACT: International Journal of Research in Engineering & Technology (IMPACT: IJRET) Vol., Issue 3, Aug 23, - Impact Journals RECYCLED MICRO HYDROPOWER GENERATION USING HYDRAULIC RAM PUMP (HYDRAM) C.
More informationPerforming a Steady Flow Analysis
C H A P T E R 7 Performing a Steady Flow Analysis This chapter discusses how to calculate steady flow water surface profiles. The chapter is divided into two parts. The first part discusses how to enter
More informationExperiment # 3: Pipe Flow
ME 05 Mechanical Engineering Lab Page ME 05 Mechanical Engineering Laboratory Spring Quarter 00 Experiment # 3: Pipe Flow Objectives: a) Calibrate a pressure transducer and two different flowmeters (paddlewheel
More informationLECTURE 28 to 29 ACCUMULATORS FREQUENTLY ASKED QUESTIONS
LECTURE 28 to 29 ACCUMULATORS FREQUENTLY ASKED QUESTIONS 1. Define an accumulator and explain its function A hydraulic accumulator is a device that stores the potential energy of an incompressible fluid
More informationPerformance Improvement of Pump-turbine for Large Capacity Pumped Storage Power Plant in USA
Performance Improvement of Pump-turbine for Large Capacity Pumped Storage Power Plant in USA 198 Performance Improvement of Pump-turbine for Large Capacity Pumped Storage Power Plant in USA 300-MW Pump-turbine
More informationA Comparison of Analytical and Finite Element Solutions for Laminar Flow Conditions Near Gaussian Constrictions
A Comparison of Analytical and Finite Element Solutions for Laminar Flow Conditions Near Gaussian Constrictions by Laura Noelle Race An Engineering Project Submitted to the Graduate Faculty of Rensselaer
More informationDynamic Torque Models for Quarter-Turn Air-Operated Valves
Dynamic Torque Models for Quarter-Turn Air-Operated Valves M. S. Kalsi, B. Eldiwany, V. Sharma, D. Somogyi Kalsi Engineering, Inc. Abstract The U.S. nuclear power plants are currently developing and implementing
More informationDEVELOPMENT OF A TWIN SCREW EXPRESSOR AS A THROTTLE VALVE REPLACEMENT FOR WATER-COOLED CHILLERS
DEVELOPMENT OF A TWIN SCREW EXPRESSOR AS A THROTTLE VALVE REPLACEMENT FOR WATER-COOLED CHILLERS J J Brasz, Carrier Corporation, Syracuse, NY, 13221, USA joost.j.brasz@carrier.utc.com I K Smith and N Stosic
More informationCENTRIFUGAL PUMP SELECTION, SIZING, AND INTERPRETATION OF PERFORMANCE CURVES
CENTRIFUGAL PUMP SELECTION, SIZING, AND INTERPRETATION OF PERFORMANCE CURVES 4.0 PUMP CLASSES Pumps may be classified in two general types, dynamic and positive displacement. Positive displacement pumps
More informationIntroduction. Chapter 1. 1.1 The Motivation
Chapter 1 Introduction 1.1 The Motivation Hydroelectric power plants, like real systems, have nonlinear behaviour. In order to design turbine controllers, it was normal practice in the past, when computer
More informationCONVERGE Features, Capabilities and Applications
CONVERGE Features, Capabilities and Applications CONVERGE CONVERGE The industry leading CFD code for complex geometries with moving boundaries. Start using CONVERGE and never make a CFD mesh again. CONVERGE
More informationExperimentation and Computational Fluid Dynamics Modelling of Roughness Effects in Flexible Pipelines
Experimentation and Computational Fluid Dynamics Modelling of Roughness Effects in Flexible Pipelines Sophie Yin Jeremy Leggoe School of Mechanical and Chemical Engineering Daniel Teng Paul Pickering CEED
More informationHEAVY OIL FLOW MEASUREMENT CHALLENGES
HEAVY OIL FLOW MEASUREMENT CHALLENGES 1 INTRODUCTION The vast majority of the world s remaining oil reserves are categorised as heavy / unconventional oils (high viscosity). Due to diminishing conventional
More informationFLUID FLOW Introduction General Description
FLUID FLOW Introduction Fluid flow is an important part of many processes, including transporting materials from one point to another, mixing of materials, and chemical reactions. In this experiment, you
More information2. Parallel pump system Q(pump) = 300 gpm, h p = 270 ft for each of the two pumps
Pumping Systems: Parallel and Series Configurations For some piping system designs, it may be desirable to consider a multiple pump system to meet the design requirements. Two typical options include parallel
More informationME 239: Rocket Propulsion. Over- and Under-expanded Nozzles and Nozzle Configurations. J. M. Meyers, PhD
ME 239: Rocket Propulsion Over- and Under-expanded Nozzles and Nozzle Configurations J. M. Meyers, PhD 1 Over- and Underexpanded Nozzles Underexpanded Nozzle Discharges fluid at an exit pressure greater
More informationwww.klmtechgroup.com TABLE OF CONTENT
Page : 1 of 38 Project Engineering Standard www.klmtechgroup.com KLM Technology #03-12 Block Aronia, Jalan Sri Perkasa 2 Taman Tampoi Utama 81200 Johor Bahru Malaysia CAUSTIC AND CHEMICAL TABLE OF CONTENT
More informationAvoiding Pressure Surge Damage in Pipeline Systems
Avoiding Pressure Surge Damage in Pipeline Systems Presented by Geoffrey D Stone CP Eng FIE Aust Geoffrey Stone has worked for over thirty years in Australia, SE Asia and the Middle East as a piping engineer.
More informationUnit 24: Applications of Pneumatics and Hydraulics
Unit 24: Applications of Pneumatics and Hydraulics Unit code: J/601/1496 QCF level: 4 Credit value: 15 OUTCOME 2 TUTORIAL 3 HYDRAULIC AND PNEUMATIC MOTORS The material needed for outcome 2 is very extensive
More informationLecture 22 Example Culvert Design Much of the following is based on the USBR technical publication Design of Small Canal Structures (1978)
Lecture 22 Example Culvert Design Much of the following is based on the USBR technical publication Design of Small Canal Structures (1978) I. An Example Culvert Design Design a concrete culvert using the
More informationVarious Technics of Liquids and Solids Level Measurements. (Part 3)
(Part 3) In part one of this series of articles, level measurement using a floating system was discusses and the instruments were recommended for each application. In the second part of these articles,
More informationNEBB STANDARDS SECTION-8 AIR SYSTEM TAB PROCEDURES
NEBB STANDARDS SECTION-8 AIR SYSTEM TAB PROCEDURES 8.1 INTRODUCTION Testing, adjusting, and balancing of HVAC systems can best be accomplished by following a series of systematic procedures. The NEBB TAB
More informationHydraulic losses in pipes
Hydraulic losses in pipes Henryk Kudela Contents 1 Viscous flows in pipes 1 1.1 Moody Chart.................................... 2 1.2 Types of Fluid Flow Problems........................... 5 1.3 Minor
More informationCE 6303 MECHANICS OF FLUIDS L T P C QUESTION BANK PART - A
CE 6303 MECHANICS OF FLUIDS L T P C QUESTION BANK 3 0 0 3 UNIT I FLUID PROPERTIES AND FLUID STATICS PART - A 1. Define fluid and fluid mechanics. 2. Define real and ideal fluids. 3. Define mass density
More informationHydraulic Transients used for Leakage Detection in Water Distribution Systems
Hydraulic Transients used for Leakage Detection in Water Distribution Systems Dídia Covas and Helena Ramos Instituto Superior Técnico, Dept. Civil Engineering, Lisbon, Portugal ABSTRACT The current paper
More informationA Strategy for Teaching Finite Element Analysis to Undergraduate Students
A Strategy for Teaching Finite Element Analysis to Undergraduate Students Gordon Smyrell, School of Computing and Mathematics, University of Teesside The analytical power and design flexibility offered
More informationChapter 19 Purging Air from Piping and Vessels in Hydrocarbon Service
BP Lower 48 Onshore Operations Safety Manual Page 4.19 1 Chapter 19 Purging Air from Piping and Vessels in Hydrocarbon Service I. General Requirements A. After motor vehicle accidents and underground excavation
More informationThe performance of centrifugal pumps when pumping ultra-viscous paste slurries
The performance of centrifugal pumps when pumping ultra-viscous paste slurries by J. Crawford*, F. van Sittert, and M. van der Walt Synopsis Significant advances have been made in the design of centrifugal
More informationAN ANALYTICAL MODEL FOR WATER PROFILE CALCULATIONS IN FREE SURFACE FLOWS THROUGH ROCKFILLS
JOURNAL OF THEORETICAL AND APPLIED MECHANICS 53, 1, pp. 209-215, Warsaw 2015 DOI: 10.15632/jtam-pl.53.1.209 AN ANALYTICAL MODEL FOR WATER PROFILE CALCULATIONS IN FREE SURFACE FLOWS THROUGH ROCKFILLS Amel
More informationCEE 370 Fall 2015. Laboratory #3 Open Channel Flow
CEE 70 Fall 015 Laboratory # Open Channel Flow Objective: The objective of this experiment is to measure the flow of fluid through open channels using a V-notch weir and a hydraulic jump. Introduction:
More informationWater Hammer. KSB Know-how, Volume 1
Water Hammer KSB Know-how, Volume 1 Contents Table of Contents Page 1 Introduction.....................................3 2 General - The Problem of Water Hammer..............4 2.1 Steady and Unsteady Flow
More informationChapter 8: Flow in Pipes
Objectives 1. Have a deeper understanding of laminar and turbulent flow in pipes and the analysis of fully developed flow 2. Calculate the major and minor losses associated with pipe flow in piping networks
More informationinter.noise 2000 The 29th International Congress and Exhibition on Noise Control Engineering 27-30 August 2000, Nice, FRANCE
Copyright SFA - InterNoise 2000 1 inter.noise 2000 The 29th International Congress and Exhibition on Noise Control Engineering 27-30 August 2000, Nice, FRANCE I-INCE Classification: 2.1 WHISTLING PHENOMENA
More informationMaterial taken from Fluid Power Circuits and Controls, John S. Cundiff, 2001
Pressure Control Chapter 3 Material taken from Fluid Power Circuits and Controls, John S. Cundiff, 2001 Introduction Pressure control is a key element in the design of any circuit. Used correctly, it can
More informationRESEARCH PROJECTS. For more information about our research projects please contact us at: info@naisengineering.com
RESEARCH PROJECTS For more information about our research projects please contact us at: info@naisengineering.com Or visit our web site at: www.naisengineering.com 2 Setup of 1D Model for the Simulation
More informationManufacturing Equipment Modeling
QUESTION 1 For a linear axis actuated by an electric motor complete the following: a. Derive a differential equation for the linear axis velocity assuming viscous friction acts on the DC motor shaft, leadscrew,
More informationENERGY TRANSFER SYSTEMS AND THEIR DYNAMIC ANALYSIS
ENERGY TRANSFER SYSTEMS AND THEIR DYNAMIC ANALYSIS Many mechanical energy systems are devoted to transfer of energy between two points: the source or prime mover (input) and the load (output). For chemical
More informationSelect the Right Relief Valve - Part 1 Saeid Rahimi
Select the Right Relief Valve - Part 1 Saeid Rahimi 8-Apr-01 Introduction Selecting a proper type of relief valve is an essential part of an overpressure protection system design. The selection process
More informationHydraulic Transient Guidelines
Transients can introduce large pressure forces and rapid fluid accelerations into a water BY PAUL F. BOULOS, BRYAN W. KARNEY, DON J. WOOD, AND SRINIVASA LINGIREDDY distribution system. These disturbances
More informationNUCLEAR ENERGY RESEARCH INITIATIVE
NUCLEAR ENERGY RESEARCH INITIATIVE Experimental and CFD Analysis of Advanced Convective Cooling Systems PI: Victor M. Ugaz and Yassin A. Hassan, Texas Engineering Experiment Station Collaborators: None
More informationPump Maintenance - Repair
Pump Maintenance - Repair Brian Trombly Mo Droppers Cummins Bridgeway, Gaylord, Mi The basic centrifugal pump consists of two main elements: 1. The rotating element which includes an impeller and a shaft.
More informationCFD Analysis of a butterfly valve in a compressible fluid
CFD Analysis of a butterfly valve in a compressible fluid 1 G.TAMIZHARASI, 2 S.KATHIRESAN 1 Assistant Professor,Professor,Departmentment of Electronics and Instrumentation,Bharath university, chennai.
More informationCENTRIFUGAL PUMP OVERVIEW Presented by Matt Prosoli Of Pumps Plus Inc.
CENTRIFUGAL PUMP OVERVIEW Presented by Matt Prosoli Of Pumps Plus Inc. 1 Centrifugal Pump- Definition Centrifugal Pump can be defined as a mechanical device used to transfer liquid of various types. As
More informationT U R B I N E G A S M E T E R
TURBINE GAS METER TURBINE GAS METER CGT 1 2 3 4 5 6 7 Design and function page 2 General technical data page 3 Measurement outputs page 4 Dimensions and weights page 5 Performance page 7 Pressure loss
More informationChapter 28 Fluid Dynamics
Chapter 28 Fluid Dynamics 28.1 Ideal Fluids... 1 28.2 Velocity Vector Field... 1 28.3 Mass Continuity Equation... 3 28.4 Bernoulli s Principle... 4 28.5 Worked Examples: Bernoulli s Equation... 7 Example
More informationPEDAGOGY: THE BUBBLE ANALOGY AND THE DIFFERENCE BETWEEN GRAVITATIONAL FORCES AND ROCKET THRUST IN SPATIAL FLOW THEORIES OF GRAVITY *
PEDAGOGY: THE BUBBLE ANALOGY AND THE DIFFERENCE BETWEEN GRAVITATIONAL FORCES AND ROCKET THRUST IN SPATIAL FLOW THEORIES OF GRAVITY * Tom Martin Gravity Research Institute Boulder, Colorado 80306-1258 martin@gravityresearch.org
More informationWhat is the most obvious difference between pipe flow and open channel flow????????????? (in terms of flow conditions and energy situation)
OPEN CHANNEL FLOW 1 3 Question What is the most obvious difference between pipe flow and open channel flow????????????? (in terms of flow conditions and energy situation) Typical open channel shapes Figure
More informationUnsteady Pressure Measurements
Quite often the measurements of pressures has to be conducted in unsteady conditions. Typical cases are those of -the measurement of time-varying pressure (with periodic oscillations or step changes) -the
More informationChapter 20 Quasi-Resonant Converters
Chapter 0 Quasi-Resonant Converters Introduction 0.1 The zero-current-switching quasi-resonant switch cell 0.1.1 Waveforms of the half-wave ZCS quasi-resonant switch cell 0.1. The average terminal waveforms
More informationA basic introduction to steam
A basic introduction to steam FOR HOT, COLD, MOIST AND DRY, FOUR CHAMPIONS FIERCE. STRIVE HERE FOR MASTERY Milton 1666 Steam Wonderful Steam Very high heat content Recyclable Clean, non toxic Biodegradable
More informationDriven by knowledge, proven by results
Driven by knowledge, proven by results CONTENTS Introduction to Kranji 3 Oil & Gas Industry Solutions 4 Our Services 5-9 PROCESS STUDIES AND DESIGN REVIEWS BENEFITS TRAINING CFD MySep Design Software 10-11
More information