Big Hanaford Combined Cycle Plant. Calculation for Cooling Water System Transient Load Analysis. 6 November, 2001

Transcription

1 PAGE 1 OF Big Hanaford Combined Cycle Plant Calculation for Cooling Water System Transient Load Analysis 6 November, 2001

2 PAGE 2 OF CLIENT Transalta Energy Corporation PROJECT Big Hanaford Combined Cycle Plant CALCULATION TITLE CALCULATION OBJECTIVE CALCULATION FOR COOLING WATER PIPE TRANSIENT LOAD ANALYSIS. Determine maximum and minimum transient pressure, external forces acting on the flowing water in the straight pipe sections and selection of surge control devices for two pump trip and pump start with closed butterfly valve. Hydraulic transient loads, in the straight pipes between two nodes, due to pump trip, are also presented for approximate pipe stress analysis. The CW system is a standard configuration. Based on experience, the only significant transient concern is column separation after pump trip followed by column rejoining resulting in a potential large waterhammer surge pressure. I t is supposed that butterfly valves time closure is long enough not couse significant pressure surges. CALCULATION METHOD The SURGE2000 program solves the basic equations of fluid mechanics for the transient flow of an incompessible fluid in a pipe network. The wave plan approach is used. REFERENCES See Page 9 DESIGN INPUT/ASSUMPTIONS See Page 8 CONFIRMATION REQUIRED ( ) Yes No CONCLUSIONS Pump Trip: Minimum calculated vacuum at the pump outlet and upper condenser inlet and outlet for the system without protecting devices is less than 10 ft of H 2 O (4.3 psi). Water column separation will nor occur. Therefore, surge mitigation devices are not necessary. Pump Start: Water cooling pumps, when started, compress the air and vent discharge between the pump and butterfly valve to the atmosphere through the orifice. Butterfly valve opening time is 60 sec and starts opening when the air is vented from the pump discharge head and discharge

3 piping to the butterfly valve. PAGE 3 OF ISSUE NO. PREPARED REVIEWED CONFIRMATION REQUIRED ( ) By Date By Date Yes No 0 S. Pejovic Sep. 25, 01 R. Burri

4 Table of Contents PAGE 4 OF 1 ASSUMPTIONS 11 2 REFERENCES 12 3 SUMMARY Pump Trip Pump Start 13 4 METHOD OF ANALYSIS Introduction Computer Program Used SURGE ASSUMPTIONS: 15 6 STEADY OPERATION AND INPUT DATA: TWO PUMPS IN OPERATION Fluid and Piping Properties Friction Losses: Minor losses Wave Speed Pumps Condenser Cooling tower: System Orifice 1.25 in Butterfly valve Time and Increment Data Input data Isometric Piping Circulating Water System EP-25A Attachment Sh Computer scheme with pipe and node names - Attachment Sh2: Computer scheme with the flows (gpm) and hydraulic grades at nodes (ft) for steady normal operating point Attachment Sh Computer Tables of input data (See Tables 1 and 2 Pages: ) 24 7 SUMMARY OF RESULTS / CONCLUSIONS Case 0. Two Pumps Trip and Selection of Pump File for Transient Analysis Case 1. Two pump Trip Case 2. Pump Speed Controlled Shutdown 26

5 PAGE 5 OF 7.4 Case 3. Pump Startup Maximum / Minimum Transient Pressure 26 8 RECOMMENDATIONS 28 9 TWO PUMPS TRIP AND SELECTION OF PUMP FILE FOR TRANSIENT ANALYSIS TWO PUMPS TRIP 37 COMPONENT DATA 47 DATA FOR PUMP FILES 47 TAB. RESULTS TWO PUMPS CONTROLLED SHUTDOWN PUMP STARTUP Air Release Orifice 0.9/1,25 in TWO PUMPS TRIP UNBALANCED AXIAL FORCES NOTATION Momentum Equation If there are no obstructions in the fluid, and the effects of body forces are neglected, the only force acting on the fluid in the straight pipe are (see Fig. 1): the pressure forces acting over the inlet and exit areas A 1, and A 2, and the reaction force F exerted by the inner surface of the pipe on the fluid Preprocessor for TRANSIENT FORCES 88

6 PAGE 6 OF FIGURE 12 COMPUTER SCHEME FOR TRANSIENT FORCES CALCULATIONS 89 FIGURE 13. PUMP VERTICAL PIPE (PUMP NODE DOWNSTREAM OF PUMP RUNNER) 92 FIGURE 15. PUMP DISCHARGE PIPE AND BUTTERFLY VALVE OPEN 94 FIGURE 16. CONNECTING PIPE TO THE COLLECTOR 95 FIGURE 19. COLLECTOR PIPE 98 FIGURE 20. PIPE TO THE CONDENSER 99 FIGURE 21. INCLINED PIPE TO THE CONDENSER 100 FIGURE 22. PIPE TO THE CONDENSER 101 FIGURE 23. VERTICAL BRANCHING PIPE TO THE CONDENSER 102 FIGURE 24. VERTICAL BRANCHING PIPE TO THE CONDENSER 103 FIGURE 25. UPPER CONDENSER CONNECTING PIPE 104 FIGURE 26. UPPER CONNECTING PIPE 105 FIGURE 27. CONDENSER 106 FIGURE 28. CONDENSER 107 FIGURE 29. UPPER CONDENSER RETURN PIPE 108 FIGURE 30. VERTICAL CONDENSER COLLECTOR PIPE 109

7 PAGE 7 OF FIGURE 31. BRANCHING TO THE LOWER CONDENSER 110 FIGURE 32. VERTICAL PIPE TO THE LOWER CONDENSER 111 FIGURE 34. LOWER CONDENSER 113 FIGURE 35. LOWER CONDENSER 114 FIGURE 36. HORIZONTAL BECK FLOW PIPE 115 FIGURE 37. INCLINED BACK FLOW PIPE 116 FIGURE 38. BACK FLOW PIPE 117 FIGURE 39. BACK FLOW PIPE 118 FIGURE 40. BACK FLOW PIPE 119 FIGURE 41. INCLINED BACK FLOW PIPE 120 FIGURE 42. HORIZONTAL DISTRIBUTION PIPE TO THE COOLING TOWER ATTACMENTS 124 Pumps 124 P1 - Ingersoll-Dresser Pumps Proposed Performance 124 P2 - Dave Mathewson fax, Aug. 07, 01, - (Pump data: Specific speed and Pump-Motor Inertia) 124 P3 Pump 42EPM-1 stage Estimated Dimensions and Weights 124 P4 - To Richard Burri / From David R. Mathewson (Pump Startup) 124 Condenser 124 C1 Surface Condenser Specification Sheet Guarantee Case 124 C2 Condenser Data 124

8 PAGE 8 OF Schemes 124 Sh1 Isometric Piping circulating Water, EP-25A 124 Sh2 Computer Program Pipe and Nodes Names 124 Sh3 Computer Calculated Steady Flows and Hydraulic Grades 124 Two Pump Trip 124 TPT1 Big Hanaford Combined Cycle Plant Two pumps trip Maximum and minimum grade lines 124 Cooling Tower 124 CT1 - Head Loss Calculations 124 s To/From Dr. Don Wood: Questions and Answers on pump speed and torque calculation 124 Table of Figures Figure 1. Pump Four Quadrant Characteristics for specific speeds: 3725 (ID 4), 4409 (ID 5) and 4390 (Manufaturer s data) Figure 2.. Pump Four Quadrant Characteristics for specific speeds: 5203 (ID 6), 6792 (ID 7) and 5460 (Calculated, see attecment P1 - Ingersoll-Dresser Pumps Proposed Performance. ) Figure 3. Computer Scheme with Pipe and Node Labels Computer Scheme with Flows in Pipes and Hydraulic Grade Lines at Nodes Figure 5. Charts of Two Pumps Trip Pump File ID Figure 6. Charts of Two Pumps Trip Pump File ID Figure 7. Selection of Pump Four Characteristics File for Transient Calculations Figure 8. Two Pumps Controlled Shutdown Comparison to Two Pumps Trip...64 Figure 9. Pump Startup. Air Outflow Orifice 1.25 in Figure 10. Pump Startup. Air Outflow Orifice 1.25 in Figure 11 Determination of the forces acting on a straight pipe Figure 12 Computer scheme for transient forces calculations Figure 13. Pump vertical pipe (Pump node downstream of pump runner) Figure 14. Pump vertical pipe (Pump node downstream of pump runner) Figure 15. Pump discharge pipe and butterfly valve open Figure 16. Connecting pipe to the collector Figure 17. Connecting pipe to the collector Figure 18. Pump discharge pipe and butterfly valve open Figure 19. Collector pipe Figure 20. Pipe to the condenser Figure 21. Inclined pipe to the condenser Figure 22. Pipe to the condenser Figure 23. Vertical branching pipe to the condenser Figure 24. Vertical branching pipe to the condenser Figure 25. Upper condenser connecting pipe Figure 26. Upper connecting pipe Figure 27. Condenser Figure 28. Condenser Figure 29. Upper condenser return pipe

9 PAGE 9 OF Figure 30. Vertical condenser collector pipe Figure 31. Branching to the lower condenser Figure 32. Vertical pipe to the lower condenser Figure 33. Connecting pipe to the lower condenser Figure 34. Lower condenser Figure 35. Lower condenser Figure 36. Horizontal beck flow pipe Figure 37. Inclined back flow pipe Figure 38. Back flow pipe Figure 39. Back flow pipe Figure 40. Back flow pipe Figure 41. Inclined back flow pipe Figure 42. Horizontal distribution pipe to the cooling tower Figure 43. Horizontal distribution pipe to the cooling tower including pressure and bend forces turning flow from horizontal into vertical direction Figure 44. Horizontal pipe butterfly valve closed...

10 PAGE 10 OF CLIENT Transalta Energy Corporation PROJECT Big Hanaford Combined Cycle Plant I T E M RUN NUMBER DATE OF RUN S T A T U S * PREPARED CHECKED BY DATE BY DATE 0 SURGE G S. Pejovic Sep. 25, 01 R. Burri Sep. 25, 01 1 SURGE Sep. 25, 01 2 SURGE SURGE SURGE G = GOOD RUN N = NULLIFIED RUN I T E M MACHINE USED 1 WS ID WORD 97 SR SOFTWARE OR PROGRAMS NAME REFERENCE NUMBER, VERSION AND LEVEL COMPUTER JOB NUMBER I T E M DOCUMENT STORAGE STORAGE MEDIUM V: Network STORAGE LOCATION C:\STAN\S & W\NewSurge2001\ReprtFin\BHCCP CWPTLA - Pg 5-NEW.doc

11 1 ASSUMPTIONS Total Cooling Water Flow Rate is based on Condenser requirement of 57,200 usgpm, plus Heat Exchanger Flow Rate of 2,000 usgpm = Total Flow of 59,200 usgpm: x 1.05 SF = Total Rated Flow of 62,160 usgpm for two (2) Pumps in Parallel operation. Total Rated Flow / Pump = 31,080 usgpm. Wave Propagation is calculated for water without presence of even small quantities of air, which significantly reduce the wave propagation speed in the pipes. Pump Four Quadrant File is selected for specific speed 4409 (ID 5) which is nearest to the pump specific speed Ns = 4390 supplied by manufacturer. SURGE2000 program has 8 files based on experimental available data. The pump file is customized to the cooling water pump by the Rated Head, Rated Flow, Rated Speed and Inertia (corresponding specific speed 5460 not confirmed by manufacturer). Water cooling pumps have a non-reverse ratchet. SURGE2000 simulate (i) pump trip: the pump speed following loss of power is calculated using dynamic analysis including torque, inertia, etc. If the butterfly valve at the pump outlet does not close, pump turns into the turbine operation with reverse flow and speed of rotation runaway. (ii) Program simulates pump shutdown, pump start up, pump shutdown followed by startup (table of rated) changing the speed of rotation input: speed versus time. Really pump transient operating point and corresponding torque controls speed, as it is programmed in the case of pump trip. Analysis was complete as follows: Pump trip with selected pump file ID 5 in the region of specific speed between 4390 and 5460, which delivered a bit lower pressure at the condensers and pump outlets. Input table: pump speed versus time was selected to follow pump trip pressure drop, estimating the time when pump speed should be zero. Results of analysis is not enclosed into this report. Analysis was further continued with the selected input data table. Condenser is simulated by the equivalent pipe of the same length as 1 in pipes (total number 6,740), wave propagation speed, flow velocity and pressure drop. Valves simulate cooling tower sprsy nozels: pressure drop 2 ft at full Rated Flow. PAGE 11 OF CONFIRMATION REQUIRED ( ) Yes No

12 REFERENCE NUMBER DESIGN INPUT PAGE 12 OF CONFIRMATION REQUIRED ( ) Yes No 1. INGERSOLL-DRESSER PUMPS PROPOSED PERFORMANCE 2. Dave Mathewson fax, Aug. 07, 01, - (Pump data: Specific speed and Pump-Motor Inertia) 3. Pump 42EPM-1 stage Estimated Dimensions and Weights 4 Surface Condenser Specification Sheet Guarantee Case 5 Condenser Tubes 6 Isometric Piping Circulating Water, EP-25A 7 Cooling Tower Head Loss Calculations REFERENCE NUMBER REFERENCES REFERENCES SURGE2000 computer program, Civil Engineering Software Center, University of Kentucky. This software package includes: the Surge Reference Manuel (Sept 1996) and Surge Examples (March 1993), by Dr. D.J. Wood and Dr. J.E. Funk Calculating Water Pumps (70-P-04 A/B/C), Estimated Flow and Total Dynamic Head Requirements, No CW-15, by Richard Burri Ingersoll-Dresser Pumps Proposed Performance (See Attachments) Dave Mathewson fax, Aug. 07, 01, - (Pump data: Specific speed and Pump-Motor Inertia) (See Attachments) Pump 42EPM-1 stage Estimated Dimensions and Weights (See Attachments) Surface Condenser Specification Sheet Guarantee Case (See Attachments) Head Loss Calculations (See Attachments) s To/From Dr. Don Wood: Questions and Answers on pump speed and torque calculation (See Attachments) from D. Mathenson (FLOWSERVE) to Richard Burri Pump Start-up Wylie E.B., Streeter V.L., 1993, Fluid Transients in Systems, Prentice Hall Chauldhry M.H., 1990, Applied Hydraulic Transients, Van Nostrand Reinhold Company Zucrow M.J., Hoffman J.D., 1976, Gas Dynamics, John Wiley & Sons, Inc

13 PAGE 13 OF 3 SUMMARY Total Cooling Water Flow Rate is based on Condenser and Heat Exchanger Flow requirement of 62,160 usgpm for two (2) Pumps in Parallel operation. 3.1 Pump Trip Minimum calculated vacuum at the pump outlet and upper condenser inlet and outlet for the system without protecting devices (Air/Vacuum valves) is less than 10 ft of H 2 O (4.3 psi). Water column separation will nor occur. Therefore, surge mitigation devices are not necessary. 3.2 Pump Start When started, the Circulating Water Pumps compress the air.between the pump and butterfly valve.the air (compressed) vents to the amosfere through an orifice located on the pump discharge head.. Butterfly valve opening time is 60 sec and starts opening when the air is vented from the pump discharge head and discharge piping.

14 4 METHOD OF ANALYSIS PAGE 14 OF 4.1 Introduction The hydraulic transient effects of pump trip will be investigated by computer simulation using the SURGE2000 software. The extent to which a pump trip may generate significant high or low pressures in the CW piping system is directly proportional to whether column separation can occur during shutdown and whether subsequent column rejoining can occur. The fluid response depends on the pump characteristics, the moment of inertia of the pump shaft and motor, the action of the butterfly valve and the system steady state hydraulic grade line and elevations. The computer simulation will model the interaction of these system components and effects to predict the transient pressures. The first step of this investigation is therefore to simulate the normal operation of the piping system with respect to head and flow. The steady state head vs. flow output is then used in the transient analysis module to simulate pump trip and pump startup. 4.2 Computer Program Used The SURGE2000 computer program is used for all simulations in this calculation. It is a commercially available microcomputer based software program qualified by S&W SURGE2000 The SURGE2000 computer program is a generalized commercially available hydraulic program which is used to perform both steady state and transient analyses of a piping network which may include pumps, reservoirs, air/vacuum valves, valves, bypass lines, etc. The SURGE2000 program uses the "wave plan method" with a finite difference approximation in both space and time in order to solve the governing partial differential equations. The spatial characteristics of the system are defined by the flow parameters that are ascribed to each node. One node is placed at each end of a pipe and the remainder is equally spaced along the pipe. Discretization of the flow problem with respect to time is governed by the integration time step which is usually very small. The Courant No limits the time step of the model as follows: AT min ( x i /a I ) [where: x i = nodal spacing for the pipe and a i = sonic velocity in the pipe}. The SURGE2000 cannot calculate unbalanced forces and hydraulic vibrations.

15 5 ASSUMPTIONS: PAGE 15 OF 1. Total Cooling Water Flow Rate is based on Condenser requirement of 57,200 usgpm, plus Heat Exchanger Flow Rate of 2,000 usgpm = Total Flow of 59,200 usgpm: x 1.05 SF = Total Rated Flow of 62,160 usgpm for two (2) Pumps in Parallel operation. Total Rated Flow / Pump = 31,080 usgpm. 2. Wave Propagation is calculated for water without presence of even small quantities of air, which significantly reduce the wave propagation speed in the pipes. 3. Pump Four Quadrant File is selected for specific speed 4409 (ID 5) which is nearest to the pump specific speed N s = 4390 supplied by manufacturer. SURGE2000 program has 8 files based on experimental available data. The pump file is customized to the cooling water pump by the Rated Head, Rated Flow, Rated Speed and Inertia (corresponding specific speed 5460 not confirmed by manufacturer). 4. The Circulating Water Pump Motors have a non-reverse ratchet. SURGE2000 simulates (i) pump trip: the pump speed following loss of power is calculated using dynamic analysis including torque, inertia, etc. If the butterfly valve at the pump outlet does not close, pump turns into the turbine operation with reverse flow and speed of rotation runaway. (ii) Program simulates pump shutdown, pump start up, pump shutdown followed by startup (table of rated) changing the speed of rotation input: speed versus time. Really pump transient operating point and corresponding torque controls speed, as it is programmed in the case of pump trip. Analysis was complete as follows: Pump trip with selected pump file ID 5 in the region of specific speed between 4390 and 5460, which delivered a bit lower pressure at the condensers and pump outlets. Input table: pump speed versus time was selected to follow pump trip pressure drop, estimating the time when pump speed should be zero. Results of analysis are not enclosed into this report. Analysis was further continued with the selected input data table. 5. Condenser is simulated by the equivalent pipe of the same length as 1 in pipes (total number 6,740), wave propagation speed, flow velocity and pressure drop. 6. Valves simulate cooling tower spray nozzels: pressure drop 2 ft at full Rated Flow.

16 6 STEADY OPERATION AND INPUT DATA: TWO PUMPS IN OPERATION. PAGE 16 OF 6.1 Fluid and Piping Properties Vapor Head Kinematic Viscosity = (ft gage) = 1.09 E -05 (f 2 /sec) The condenser incoming fluid temperature is 74 F and the outgoing temperature is 94 F (Ref. 6.2). The sonic velocity computed in Section would be slightly different if the fluid properties at these temperatures were used. Wave Propagation is calculated for water without presence of even small quantities of air, which significantly reduce the wave propagation speed in the pipes Friction Losses: Hazen Williams equation was used to estimate the system friction loses: h LP = 4.73LQ C D h LP = Friction loss (ft) C = flow coefficient (C = 100 used in calculations) Q = Flow (cfs) D = diameter of pipe (ft) L = length of pipe (ft) Minor losses Minor losses are calculated as h LM = Minor loss (ft) V = Flow velocity ((ft/s) g = acceleration of gravity (ft/s 2 ) M = Resistance coefficient 2 V h LM = M 2g

17 6.1.3 Wave Speed PAGE 17 OF Wave propagation speed is obtained using SURGE2000 Tools: Wave Speed in Circular Pipes (Poisson Ratio 0.25; no presence of air in water) c = E K f E f D ρ 1 + Ect f c = propagation speed (ft/s) Kf = Coefficient of restraint for longitudinal pipe movement E r = elastic modulus of water (psi) E c = elastic modulus of conduit (psi) D = diameter of pipe (ft) t = pipe thickness (ft) Pumps Flowsreve (Ingersoll-Dresser) Pumps characteristics supplied by manufacturer cover only normal operating zone of flow: 0 to gpm (see Attachments P1, P2 and P3). Rated data: Discharge Capacity: gpm Head: 65.1 ft Efficiency: 87.0 % NPSHR: 25 FT Speed: 710 rpm Pump type: 42EPM Specific speed: 4390 (Manufacturer s data) Calculated specific speed: 5460 (calculated for rated data) Motor moment of inertia: 1072 lb-ft 2 Pump moment of inertia: 528 lb-ft 2 Pump outlet pipe elevation: 261 ft Pump inlet elevation: ft Impeller elevation: ft Min, water elevation: 254 ft Pump Four Quadrant File is selected for specific speed 4409 (ID 5) which is nearest to the pump specific speed Ns = 4390 supplied by manufacturer (see Figs?). SURGE2000 program has 8 files based on experimental available data. The pump file is customized to the cooling water pump by the Rated Head, Rated Flow, Rated Speed and Inertia (corresponding specific speed 5460 not confirmed by manufacturer).

18 PAGE 18 OF Figure 1. Pump Four Quadrant Characteristics for specific speeds: 3725 (ID 4), 4409 (ID 5) and 4390 (Manufaturer s data) Pump Four Quadrant Characteristics ID / Ns (Specific Speed) WH/WB Series1 ID 4 / 3725 Series2 Series3 ID5 / 4409 Series4 Series Series Q

19 PAGE 19 OF Figure 2.. Pump Four Quadrant Characteristics for specific speeds: 5203 (ID 6), 6792 (ID 7) and 5460 (Calculated, see attecment P1 - Ingersoll-Dresser Pumps Proposed Performance. ) Pump Four Quadrant Characteristics 4 3 ID / Ns Specific Speed WH/WB Ser i es 1 ID6 / 5203 Ser i es 2 Ser i es 3 Ser ID7 i/ es Ser i es Ser i es q

20 PAGE 20 OF The Circulating Water Pump Motors have a non-reverse ratchet. SURGE2000 simulate (i) pump trip: the pump speed following loss of power is calculated using dynamic analysis including torque, inertia, etc. If the butterfly valve at the pump outlet does not close, pump turns into the turbine operation with reverse flow and speed of rotation runaway. (ii) Program simulates pump shutdown, pump start up, pump shutdown followed by startup (table of rated) changing the speed of rotation input: speed versus time. Really pump transient operating point and corresponding torque controls speed, as it is programmed in the case of pump trip. Analysis was complete as follows: Pump trip with selected pump file ID 5 in the region of specific speed between 4390 and 5460, which delivered a bit lower pressure at the condensers and pump outlets. Input table: pump speed versus time was selected to follow pump trip pressure drop, estimating the time when pump speed should be zero. Analysis was further continued with the selected input data table. Pump start calculations Condenser Condenser is simulated by the equivalent pipe of the same length as 1 in pipes (total number 6,740), wave propagation speed, flow velocity and pressure drop (see Attachment C1 and C2). Design conditions, water side: Water flow: gpm Pressure drop: 23.1 ft of 70 0 F Temperature, water in: F Temperature, water out: F Number of passes: 2 Pipe inlet/outlet elevation, higher: ft Pipe inlet/outlet elevation, lower: ft Number of tubes: 6740 Tube diameter O.D. 1 in Tube wall thickness: in (22 BWG) Water velocity: 8 ft/sec Tubes material: 304L S.S. Equivalent pipe: Diameter: Length: Wave speed: 39 in 41 ft 4142 ft/s

21 Water velocity: 8.0 ft/sec Loss coefficient: 11 Flow coefficient: 100 Condenser has two inlets and two outlets; each has two equivalent pipes of 41 ft length. PAGE 21 OF Cooling tower: Valves simulate cooling tower spray nozzelss: pressure drop 2 ft at full Rated Flow (see Attachment CT1). Main data: Number of cooling towers: 5 Elevation of nozzles: ft Nozzles pressure: 2 ft System Attachments showing piping system: Attachment Sh1: Isometric Piping Circulating Water System Attachment Sh2: Computer scheme with pipe and node names Attachment Sh3: Computer scheme with the flows (gpm) and hydraulic grades at nodes (ft) Orifice 1.25 in The Circulating Water Pumps, when started, compress and vent the air between the pump and the butterfly valve to the atmosphere through a 1.25 in orifice. When the air is vented (aqpproximatly 10 seconds after pump start, depending on the selected oriffice size), the Butterfly Valves can be opened (One at a time) Butterfly valve Closing / opening time is 60 sec. Opening of the valve will start 10 seconds after the pump startup. Pump shutdown occurs when the butterfly valve is closed. Main data: Inside diameter: Elevation: 35 in 261 ft

22 Closing time: Opening time: 60 sec 60 sec PAGE 22 OF Time and Increment Data Total Simulation Time and Time Increment can be changed and adapted to the analyzed case. Figure 3. Computer Scheme with Pipe and Node Labels 4. Computer Scheme with Flows in Pipes and Hydraulic Grade Lines at Nodes

23 PAGE 23 OF 6.2 Input data Isometric Piping Circulating Water System EP-25A Attachment Sh Computer scheme with pipe and node names - Attachment Sh2: Computer scheme with the flows (gpm) and hydraulic grades at nodes (ft) for steady normal operating point Attachment Sh3

24 6.2.4 Computer Tables of input data (See Tables 1 and 2 Pages: ) PAGE 24 OF

25 PAGE 25 OF 7 SUMMARY OF RESULTS / CONCLUSIONS The hydraulic transient analysis of the Big Hanaford Combined Cycle Plant cooling system was performed using the SURGE2000 computer program to determine if water column separation and water column rejoining with subsequent significant pressure surges can occur after pump trip. The results of the analysis show that water column separation and subsequent water column rejoining will not occur. Unbalanced axial forces on elbow pairs due to pump trip are not analyzed. The Circulating Water Pumps, when started, compress and vent the air between the pump and the butterfly valve to the atmosphere. Pressure waterhammer force on the butterfly valve has been calculated. Three hydraulic cases are simulated as follows: Case 0 Two Pumps Trip and Selection of Pump File for Transient Analysis. Case 1 - Pump operation followed by 2-pump trip (to full runaway of the pumps pumps without non revese ratchets). Case 2 - Pump operation followed by 2-pump shutdown pump speed reduced from 710 rpm to 0 rpm in 5 seconds (pump with non reverse ratchet). Case 3 - Pump startup and air vent through 2 in pipe with the outlet orifice 1.25 in. Case Input File Output file Date/Time Printed Input / Output Results 0 Tr2PID5.P2K Tr2PID6.P2K Tr2PID5.OUT Tr2PID6.OUT Table 4, Figs. 1, 2, and 3? 1 Tr2PID5.P2K Tr2PID5.OUT Table 4, Figs.? 2 SpSelect.P2K SpSelect.OUT Figs? 3 StOr125.P2K StOr125.P2K Table 6, Figs? The steady state (hydraulic grade line vs. flow) results and one pump operation were obtained using the SURGE2000 steady state module and show very good agreement with the steady state hydraulic calculation presented in Calculating Water Pumps (70-P-04 A/B/C), Estimated Flow and Total Dynamic Head Requirements, No CW-15. The steady state hydraulic results are automatically input into the SURGE2000 transient module to simulate pump trip.

26 7.1 Case 0. Two Pumps Trip and Selection of Pump File for Transient Analysis PAGE 26 OF This case is simulated for 30 seconds to see the effect of 2 pumps operation followed by 2-pump trip. A review of the nodes AV-H (condenser outlet upper flange at elevation ft), Pump-1 and Pump-2 (pump outlet pipe at elevation 261 ft), see Figs. 1, 2, and 3, show that the difference is very small so any of these two pump files can be used for further calculations. Pump file ID 5 was selected. 7.2 Case 1. Two pump Trip This case is simulated for 30 seconds to see the effect of 2 pumps operation followed by 2-pump trip. A review of the node AV-H (condenser outlet upper flange at elevation ft) pressure plot in Fig. 1 and Table 4 reveals that the head at this node drops to pressure 8.8 ft (> than vapor head ft gage) at approximately 1 second after pump trip. A review of the node Pump-1 and Pump-2 (pump outlet pipe at elevation 261 ft)) pressure plot in Fig. 1 and Table 4 reveals that the head at these nodes drop to pressure 6.3 ft (> than vapor head ft gage) at approximately 2 seconds after pump trip. Therefore, surge mitigation devices are not necessary. 7.3 Case 2. Pump Speed Controlled Shutdown The Circulaing Water Pump Motors have non-reverse ratchets (preventing pump and motor reverse rotation). Speed deceleration was selected to calculate slightly smaller pressure at the pump and condenser outlets. Results of computer simulation show that minimum pressures occur at the condenser outlet and pump discharge before pump rotation speed shutdown (See Fig. 4???). 7.4 Case 3. Pump Startup Furing start, the CirculatingWater Pumps compress and vent the air in the pump discharge (between pump and butterfly valve) to the atmosphere through a 2 in pipe with an outlet orifice 1.25 in diameter. Butterfly valve opening time is 60 sec and starts openingaft3er the air in the discharges is vented.. Initial volume of compressed air is 30 ft 3 (87 SCF). Maximum pressure at the butterfly valve is = 79 psi. The maximum design pressure for the pipes is 100 psi (See Table 6??? and Figs. 5 and 6???). In trial operation final orifice size should be selected 7.5 Maximum / Minimum Transient Pressure

27 PAGE 27 OF The maximum transient pressure experienced by the CW system due to pump trip is not greater than the steady state pressure. The minimum transient pressure experienced by the CW system due to pump trip is about 8.8 ft gage (vapor pressure = ft gage) at the condenser outlet.

28 8 RECOMMENDATIONS PAGE 28 OF During trial operation of the pump start-up, the air outlet orifice should be selected to optimize pump startup time and pressure surges. Generally (i) small orifice: long starting time, low pressure surges, (ii) big orifice: short starting time, big pressure surges. Air outflow will be at sonic speed followed by high frequency noise and sound waterhammer at the end of air outflow. During start-up of the CW system air must be purged out of the system to avoid water hammer concerns. The Butterfly Valve starts opening when the pump has vented the air from the pump discharge line. Normal system start-up procedures (especially venting procedures) must be followed at all times. During start-up of the CW system after pump trip, air must be purged from the system to avoid water hammer concerns. It is recommended that normal system start-up procedures (especially venting procedures) be followed after a pump trip. The Butterfly Valve operators have maximum operating time of 60 second It is recommended that this naximum operating time be used.

29 Tables of Input Data and Steady Operating Point Table 1. Nodes Elevation, Hydraulic Grade and pressure Head R E S U L T S F O R Case NODE RESULTS (Case-0) Node Elevation HydGrade PresHead AV-H AV-L BV BV BV J J J J J J J J J J J J J J J J J J J J J J J J Pump Pump Pump PAGE 29 OF

30 PAGE 30 OF Table 2. Pipes, End nodes, Lengths, Diameters and Minor Loss Coefficients R E S U L T S F O R Case PIPE RESULTS (Case-0) Pipe StartNode EndNode Length Diameter MLCoeff P-1 J-4 J P-10 J-31 J P-11 J-21 J P P P-14 J-3 J P-15 J-41 J P-16 AV-L J P-17 J-10 J P P-19 J-11 J P-2 J-9 J P P-21 J-22 J P P-23 Pump-1 J P-24 J-5 J P-25 BV-4 J P-26 BV-5 J P-27 BV-10 J P-28 J-6 J P-29 J-7 J P P-30 Pump-2 J P-31 Pump-3 J P P-33 J-16 J P P-35 AV-H J P-36 J-18 J P-37 J-20 J P-4 J-8 J P P P-7 J-2 J P-8 J-1 J P-9 J-3 J

31 PAGE 31 OF Table 3. Results for Two Pumps Steady Operation - Flowrate, Losses, Flow Velocities R E S U L T S F O R Case PIPE RESULTS (Case-0) Pipe StartNode EndNode FlowRate HLoss MLoss Velocity /s P-1 J-4 J P-10 J-31 J P-11 J-21 J P P P-14 J-3 J P-15 J-41 J P-16 AV-L J P-17 J-10 J P P-19 J-11 J P-2 J-9 J P P-21 J-22 J P P-23 Pump-1 J P-24 J-5 J P-25 BV-4 J P-26 BV-5 J P-27 BV-10 J P-28 J-6 J P-29 J-7 J P P-30 Pump-2 J P-31 Pump-3 J P P-33 J-16 J P P-35 AV-H J P-36 J-18 J P-37 J-20 J P-4 J-8 J P P P-7 J-2 J P-8 J-1 J P-9 J-3 J

32 9 TWO PUMPS TRIP AND SELECTION OF PUMP FILE FOR TRANSIENT ANALYSIS PAGE 32 OF Program Surge200 has 8 pump files. A pump file is a table of values defining head and torque as a function of flow and speed. These are based on available experimental data. The file selection is based on specific speeds. Transients for pumps are initialized by changing the pump speed ratio (pump speed/rated speed) or designating a pump trip where the rundown is calculated. The Circulating Water Pumps have a non-reverse ratchet. SURGE2000 simulate (i) pump trip: the pump speed following loss of power is calculated using dynamic analysis including torque, inertia, etc. If the butterfly valve at the pump outlet does not close, pump turns into the turbine operation with reverse flow and speed of rotation runaway, (ii) Program simulates pump shutdown, pump start up, pump shutdown followed by startup (table or rated) changing the speed of rotation input: speed versus time. SURGE2000 cannot graph or output table of pump speed of rotation and shaft torque, see Attachment EM1. The pump transient operating point and corresponding torque controls the pump rotatioanal speed, as it is programmed in the case of pump trip. Input data should be carefully selected to represent a real pump transient. Generally the flow reverse at a pump before the rotational speed reverse.

33 Figure 5. Charts of Two Pumps Trip Pump File ID 5 PAGE 33 OF 7.0E+4 (gpm) 6.0E+4 5.0E+4 4.0E+4 1 TWO PUMPS TRIP Two pumps trip Pump file ID 5 Pump file ID 5 (Specific speed 4409) (gpm) Two pumps trip Pump file ID 5 (Specific speed 4409) 3.0E+4 Total 40 Condenser inlet Flow 2.0E+4 Head 30 Condenser outlet 1.0E+4 Pump E+4-2.0E+4 0 Pump -3.0E Time (seconds) J-31 Pump-1 Two Pumps Trip No Air Valves (No protecting devices) Pump file ID 5 (Specific speed 4409) Time (seconds) AV-H J-16 Pump-1 1. Flow reverse at 9.1 sec, or 7.1 sec after power failure 2. Minimum pressure at pump outlet 6.3 ft 3. Minimum pressure at condenser inlet 1.3 ft 4. Minimum pressure at condenser outlet 8.8 ft

34 Figure 6. Charts of Two Pumps Trip Pump File ID 6 PAGE 34 OF (gpm) 7.0E+4 6.0E+4 5.0E+4 Two pumps trip Pump file ID 6 (Specific speed 5203) 70 (gpm) 60 Two pumps trip Pump file ID 6 (Specific speed 5203) E+4 3.0E+4 Total 2 Pump Flow 40 Condenser inlet Flow 2.0E+4 1 Pump Flow Head 30 Condenser outlet 1.0E E+4-2.0E+4 0 Pump -3.0E Time (seconds) J-31 Pump-1 Two Pumps Trip (No protecting devices) Pump file ID 6 (Specific speed 5203) Time (seconds) AV-H J-16 Pump-1 5. Flow reverse at 8.9 sec, or 6.9 sec after power failure 6. Minimum pressure at pump outlet 5.7 ft 7. Minimum pressure at condenser inlet 0.6 ft 8. Minimum pressure at condenser outlet 8.7 ft Comparison of minimum calculated pressures at the pump outlet and upper condenser inlet and outlet. Difference is very small so any of these two pump files can be used for further calculations. Pump file ID 5 was selected.

35 PAGE 35 OF Figure 7. Selection of Pump Four Characteristics File for Transient Calculations (gpm) 7.0E+4 6.0E+4 Two pumps trip Pump file ID 5 (Specific speed 4409) (gpm) 7.0E+4 6.0E+4 Two pumps trip Pump file ID 6 (Specific speed 5203) 5.0E+4 5.0E+4 2 Pump Flow 4.0E+4 3.0E+4 2 Pump Flow 4.0E+4 3.0E+4 Flow 2.0E+4 Flow 2.0E+4 1.0E+4 1.0E+4 1 Pump Flow 0 1 Pump Flow 0-1.0E+4-1.0E+4-2.0E+4-2.0E+4-3.0E Time (seconds) J-31 Pump-1-3.0E J-31 Pump-1 Time (seconds)

36 PAGE 36 OF (gpm) Two pumps trip Pump file ID 5 (Specific speed 4409) (gpm) Two pumps trip Pump file ID 6 (Specific speed 5203) Head 30 Condenser outlet Condenser Head 30 Condenser Condenser Pump 0 Pump Time (seconds) AV-H J-16 Pump Time (seconds) AV-H J-16 Pump-1

37 10 TWO PUMPS TRIP PAGE 37 OF Results of calculations are shown in Figures 1 and 2,?? Table 4?? and Attachment TPT1. Attachment TPT1 shows envelopes of hydraulic grade lines. A review of the pressure envelopes reveals that vacuum occurs: - at the condenser located at the elevation ft, nodes: J-17 and AV-H, - at the condenser located at the e,evation ft., node AV-L, and - at the pump discharges, nodes Pump-1, and Pump-2. This case is simulated for 30 seconds to see the effect of 2 pumps operation followed by 2-pump trip. A review of the node AV-H (condenser outlet upper flange at elevation ft) pressure plot in Fig. 1 and Table 4 reveals that the head at this node drops to pressure 8.8 ft (> than vapor head ft gage) at approximately 1 second after pump trip. A review of the node Pump-1 and Pump-2 (pump outlet pipe at elevation 261 ft)) pressure plot in Fig. 1 and Table 4 reveals that the head at these nodes drop to pressure 6.3 ft (> than vapor head ft gage) at approximately 2 seconds after pump trip. Therefore, surge mitigation devices are not necessary.

38 Table 4. Results and Input Data Tables in Computer Memory for Two Pumps Trip * * * * * * * * * * K Y P I P E 4 * * * * * * * * * * * * * University of Kentucky Network Modeling Software * * * * Copyrighted by KPFS 1998 * * Version /26/2000 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * PAGE 38 OF Date & Time: Wed Sep 12 09:00: INPUT DATA FILENAME C:\STAN\S&W\NEWSUR~1\Tr2pNoAV\SPSPEE~1\Tr2PID5.DT2 TABULATED OUTPUT FILENAME C:\STAN\S&W\NEWSUR~1\Tr2pNoAV\SPSPEE~1\Tr2PID5.OT2 POSTPROCESSOR RESULTS FILENAME --- C:\STAN\S&W\NEWSUR~1\Tr2pNoAV\SPSPEE~1\Tr2PID5.RS2

39 ************************************************ S U M M A R Y O F O R I G I N A L D A T A ************************************************ PAGE 39 OF U N I T S S P E C I F I E D FLOWRATE... = gallons/minute HEAD (HGL)... = feet PRESSURE... = psig P I P E L I N E D A T A STATUS CODE: XX -CLOSED PIPE CV -CHECK VALVE P I P E NODE NAMES LENGTH DIAMETER ROUGHNESS MINOR N A M E #1 #2 (ft) (in) COEFF. LOSS COEFF P-1 J-4 J P-10 J-31 J P-11 J-21 J P P P-14 J-3 J P-15 J-41 J P-16 AV-L J P-17 J-10 J P P-19 J-11 J P-2 J-9 J P P-21 J-22 J P P-23 Pump-1 J P-24 J-5 J P-25 BV-4 J P-26 BV-5 J P-27 BV-10 J P-28 J-6 J P-29 J-7 J P P-30 Pump-2 J P-31 Pump-3 J P P-33 J-16 J P P-35 AV-H J P-36 J-18 J P-37 J-20 J P-4 J-8 J P P P-7 J-2 J P-8 J-1 J P-9 J-3 J

40 P U M P/L O S S E L E M E N T D A T A PAGE 40 OF THERE IS A DEVICE AT NODE 2) Pump-1 DESCRIBED BY THE' FOLLOWING DATA: (ID= HEAD FLOWRATE EFFICIENCY (ft) (gpm) (%) THERE IS A DEVICE AT NODE 3) Pump-2 DESCRIBED BY THE' FOLLOWING DATA: (ID= HEAD FLOWRATE EFFICIENCY (ft) (gpm) (%) THERE IS A DEVICE AT NODE 4) Pump-3 DESCRIBED BY THE' FOLLOWING DATA: (ID= HEAD FLOWRATE EFFICIENCY (ft) (gpm) (%)

41 E N D N O D E D A T A PAGE 41 OF NODE NODE EXTERNAL JUNCTION EXTERNAL NAME TITLE DEMAND ELEVATION GRADE (gpm) (ft) (ft) AV-H Cond H AV-L Cond L BV-10 Butt Valve BV-4 Butt Valve BV-5 Butt Valve J J J J J-13 Pump J-14 Pump J-15 Pump J-16 Cond H J-17 Cond.H J-18 Cond L J-19 Cond L J J J J J J J J J J J J J Pump-1 Pump Pump-2 Pump Pump-3 Pump

42 O U T P U T O P T I O N D A T A PAGE 42 OF OUTPUT SELECTION: THE FOLLOWING RESULTS ARE INCLUDED IN THE TABULATED OUTPUT RESULTS FOR ALL PIPES S Y S T E M C O N F I G U R A T I O N NUMBER OF PIPES...(p) = 37 NUMBER OF END NODES...(j) = 29 NUMBER OF PRIMARY LOOPS...(l) = 1 NUMBER OF SUPPLY NODES...(f) = 8 NUMBER OF SUPPLY ZONES...(z) = 1 ============================================================================== == *** WARNING *** A PORTION OF THE SYSTEM IS DISCONNECTED FROM A FGN BY CLOSED LINES **** A FIX WILL BE ATTEMPTED THE FOLLOWING JUNCTION NODES ARE DISCONNECTED FROM THE SYSTEM DEMANDS AT THESE JUNCTION NODES ARE SET TO ZERO: J-15 PIPE NO. Case: 0 ~@BV-10 HAS BEEN OPENED TO REMOVE THE DISCONNECTION RESULTS OBTAINED AFTER 5 TRIALS: ACCURACY =

43 S I M U L A T I O N D E S C R I P T I O N (L A B E L) PAGE 43 OF P I P E L I N E R E S U L T S STATUS CODE: XX -CLOSED PIPE CV -CHECK VALVE P I P E NODE NUMBERS FLOWRATE HEAD MINOR LINE HL/ N A M E #1 #2 LOSS LOSS VELO (gpm) (ft) (ft) (ft/s)(ft/ft) P-1 J-4 J P-10 J-31 J P-11 J-21 J P-12 J-14 BV P-13 J-15 BV P-14 J-3 J P-15 J-41 J P-16 AV-L J P-17 J-10 J P-18 J-10 CT P-19 J-11 J P-2 J-9 J P-20 J-11 CT P-21 J-22 J P-22 J-12 CT P-23 Pump-1 J P-24 J-5 J P-25 BV-4 J P-26 BV-5 J P-27 BV-10 J P-28 J-6 J P-29 J-7 J P-3 J-9 CT P-30 Pump-2 J P-31 Pump-3 J P-32 J-17 AV-H P-33 J-16 J P-34 J-19 AV-L P-35 AV-H J P-36 J-18 J P-37 J-20 J P-4 J-8 J P-5 J-8 CT P-6 J-13 BV P-7 J-2 J P-8 J-1 J P-9 J-3 J ~@AV-H AV-H AV-H ******** ~@AV-L AV-L AV-L ******** ~@BV-10 BV-10 BV ~@BV-4 BV-4 BV ******** ~@BV-5 BV-5 BV ********

44 P U M P/L O S S E L E M E N T R E S U L T S PAGE 44 OF INLET OUTLET HEAD EFFIC- USEFUL INCREMTL TOTAL NAME FLOWRATE HEAD HEAD CHANGE ENCY POWER COST COST (gpm) (ft) (ft) (ft) (%) (Hp) ($) ($) Pump Pump Device "Pump-3" is closed E N D N O D E R E S U L T S NODE NODE EXTERNAL HYDRAULIC NODE PRESSURE NODE NAME TITLE DEMAND GRADE ELEVATION HEAD PRESSURE (gpm) (ft) (ft) (ft) (psi) S U M M A R Y O F I N F L O W S A N D O U T F L O W S (+) INFLOWS INTO THE SYSTEM FROM SUPPLY NODES (-) OUTFLOWS FROM THE SYSTEM INTO SUPPLY NODES NODE FLOWRATE NODE NAME (gpm) TITLE CT CT CT CT CT Pump Pump 1 Pump Pump 2 NET SYSTEM INFLOW = NET SYSTEM OUTFLOW = NET SYSTEM DEMAND = 0.00 ==============================================================================

45 Case: 1 PAGE 45 OF C H A N G E S F O R N E X T S I M U L A T I O N (Change Number = 0 ) ****** SURGE PROGRAM - VERSION 6.0 ****** Copyrighted by Dr. Don J. Wood Dr. James E. Funk Dr. Srini Lingireddy Lexington, KY, USA July 2001 ****** SURGE PROGRAM - VERSION 6.0 ****** Copyrighted by Dr. Don J. Wood Dr. James E. Funk Dr. Srini Lingireddy Lexington, KY, USA July 2001 DATE = 09/18/01 - TIME = 12:15:36 INPUT DATA FILE NAME = C:\STAN\S&W\NEWSUR~1\ReprtFin\Tr2P\SPSPEE~2\Tr2PID OUTPUT DATA FILE NAME = C:\STAN\S&W\NEWSUR~1\ReprtFin\Tr2P\SPSPEE~2\Tr2PID THE FOLLOWING DEFAULT OVERRIDES HAVE BEEN DEFINED: LIQUID SPECIFIC GRAVITY = TIME INCREMENT FACTOR = 2 FLOW CONVERSION FACTOR = HEAD CONVERSION FACTOR = START RUN AT TIME 12:15:36 TOTAL SIMULATION TIME = 30.0 sec : TIME INCREMENT = sec ENGLISH UNITS ARE SPECIFIED: FLOW in cubic feet/second & HEAD in feet **** SUMMARY OF PIPE SYSTEM DATA **** NUMBERS OF SPECIFIC ELEMENTS LINE SEGMENTS = 37 COMPONENTS = 13 JUNCTIONS = 24 BYPASS LINES = 0 SIDE ORIFICES = 0 RELIEF VALVES = 0 CHECK VALVES = 0 VARIABLE INPUTS = 4

46 LINE SEGMENT DATA PAGE 46 OF POSITION TRAVEL C/GA INITIAL SEGMENT OF ENDS INCREMENTS FLOWRATE RESISTANCE J-4 J J-31 J #J-21 J J-14 BV J-15 BV J-3 J #J-41 J AV-L #J J-10 J #J-10 CT #J-11 J J-9 #J #J-11 CT J-22 #J #J-12 CT Pump-1 J J-5 #J BV-4 J BV-5 #J BV-10 #J J-6 J J-7 #J #J-9 CT Pump-2 #J Pump-3 #J J-17 AV-H #J-16 #J J-19 AV-L AV-H #J J-18 #J #J-20 #J #J-8 #J #J-8 CT #J-13 BV #J-2 #J #J-1 #J #J-3 #J