Home

POWSIM

1. 2 gt gt o o lt STEAM TURBINE CONDENSER Figure 20 Flowsheet diagram for the triple pressure supercritical reheat steam cycle 600 TEMPERATURE C 550 500 450 400 350 300 250 200 150 100 50 0 75 150 225 300 375 450 525 600 675 750 HEAT TRANSFER MW Figure 21 TQ diagram for the triple pressure supercritical reheat steam cycle POWSIM 1 2 2000 01 03 21 3600 3500 3400 3300 3200 3100 3000 2900 2800 2700 2600 2500 2400 2300 2200 2100 2000 Figure 22 ENTHALPY KJ KG 5 000 5 250 5 500 5 750 6 000 6 250 6 500 6 750 7 000 7 250 7 500 7 750 8 000 ENTROPY KJ KG K HS diagram for the triple pressure supercritical reheat steam cycle 22 POWSIM 1 2 2000 01 03 3 INPUT DESCRIPTION In the following is a description given of the input required for a calculation in POWSIM The different menues are described separately The numbers which are referred to 1 2 and so on are the item numbers in the menues The user supplied input data are in POWSIM separated into two categories the gas turbine input data and the steam cycle input data All the input data can be saved on files and retrieved later when needed The two categories of input data are saved on separate file types see section 1 4 POWSIM 1 2 2000 01 03 23 3 1 Powsim main menu POWSIM MAIN MENU Version 1 2 Fag 66167 ITEV 0
2. F type STOP lt cr gt at the command prompt F select item 19 in the POWSIM MAIN MENU F use CTRL C When using either of the two first options the user is asked to confirm quitting POWSIM Next the screen is cleared and the screen colours is set to black background and white foreground and the system is returned to DOS Using CTRL C stops program execution at any time when running POWSIM The screen colours will remain the same as selected from within POWSIM By typing HELP lt cr gt or H lt cr gt at the command prompt a help window is displayed on the left hand side of the screen This window disappears when pressing any key and the cursor moves back to the command prompt location TO GET THIS WINDOW REFRESH THE SCREEN INPUT ALL ITEMS INPUT ITEM NR ITEM INPUT QUIT THE QUIT THE MENU STOP THE PROGRAM Help window in the menues POWSIM 1 2 2000 01 03 1 6 Menu structure The menu structure in POWSIM is shown in Figure 1 on page 7 The dotted lines in Figure 1 indicates that it possible to go from the CALCULATION amp OUTPUT menu to the STEAM CYCLE INPUT SUPPLEMENTARY FIRING and GAS TURBINE INPUT CHECK menues POWSIM MAIN MENU STEAM CYCLE INPUT HEAT RECOVERY STEAM GENERATOR PREHEATING SYSTEM AND CONDENSER STEAM TURBINE PUMPS Figure 1 structure in POWSIM POWSIM 1 2 2000 01 03 2 STEAM CYCLE CONFIGURATIONS When specifying the steam cycle in POWSIM a numb
3. amp exergy analysis results on screen The results from the overall heat balance and exergy analysis are displayed There are a number of sections for the presentation of the results and these are o Heat balance for the steam cycle HRSG Steam turbine and condenser Exergy analysis for HRSG Exergy analysis for steam turbine Exergy analysis for condenser Exergy loss summary Main exergy losses sorted by size POWSIM 1 2 2000 01 03 43 Some of the sections are displayed on one screen page while others are displayed on multiple pages The user can go between any of the different sections by pressing the appropriate key look at the bottom line on the screen By simply pressing lt cr gt the sections are displayed in the succession shown above By typing E exit POWSIM returns to the CALCULATION amp OUTPUT menu 8 Exergy analysis results to file The results described for item 7 are written to a file The user is asked for a file name no extension POWSIM adds the extension XRY to the user supplied file name 9 Not used 10 Make the heat recovery TQ diagram plotter file HP GL The TQ diagram for the HRSG is written to a file with the HP GL format This format is accepted by many pen plotters as well as some laser writers It is also possible to include this plotter file in many word processing systems like WordPerfect as you can see in this manual The user is asked for a file name no extension POWSIM adds th
4. and reads them automaticly when the program is started as shown above Reading input files when running POWSIM is of course also possible see section 0 0 and 0 C POWSIM gt POWSIM filename PGT filename PDT cr C POWSIM gt POWSIM filename PDT filename PGT cr C POWSIM gt POWSIM filename PGT cr C POWSIM gt POWSIM filename PDT cr 1 4 File types There are eight types of files with different meanings to the POWSIM system These are distinguished by the file extension 1 2 3 4 5 6 7 8 9 POWSIM EXE PGT PDT RES XRY HPT HPH PRO POWSIM LOG 10 POWSIM DEF 11 HS SAT 1 POWSIM EXE is the executable code for the POWSIM program 2 Files with the extension PGT are input files containing information about the gas turbine data that are used for two purposes in POWSIM information about the heat source for the steam cycle gas temperature gas flow rate and gas composition POWSIM 1 2 2000 01 03 in order to calculate combined cycle performance the PGT files contain information about power output fuel consumption and auxiliary power demand for the gas turbine s This is a sequential ASCII file and may be edited with an editor such as Turbo Pascal BRIEF or others However this is not recommended If the file is to be changed outside POWSIM do not remove any lines or change the succession of the lines The information in this file can be ch
5. 2 lt cr gt UPPER STEP FOR PRESSURE 1 EL 3 3 6 1 cr ERATURE BEHIND GAS TURBINE i 561 4 ENT VALUE OF SUPPL FIRING TEMPERATURE E 570 0 R UPPER STEP FOR SUPPL FIRING TEMPERATURE 570 580 10 cr ER OF CALCULATIONS 528 DO YOU WANT TO REVISE INPUT Y N Optimization input bold characters are user supplied input 4 Not used 5 Computational results on screen The results from the cycle and heat transfer area calculations are displayed There are a number of sections for the presentation of the results and these are Main data Exhaust gas data HRSG Deaerator and preheating system HRSG heat transfer HRSG heat transfer area Steam turbine Pumps Condenser Some of sections are displayed on one screen page while others are displayed on multiple pages The user can go between any of the different sections by pressing the appropriate key By typing H help the user can see which keys to use By simply pressing lt cr gt the sections are displayed in the succession shown above By typing E exit POWSIM returns to the CALCULATION amp OUTPUT menu 6 Computational results to file The results described for item 5 are written to a file The user is asked for a file name no extension POWSIM adds the extension RES to the user supplied file name The user can specify which sections of the results to be written to the file 7 Heat balance
6. 2 the number of pressure levels is restricted to 7 This item is for information only and cannot be changed by selecting the item 2 Number of pressure levels In POWSIM the number of pressure levels is defined as the number of HRSG steam exit points feeding the steam turbine The steam reheat is always pressure level 2 The number of pressure levels has to be greater than or equal to 1 and less than or equal to item 1 3 Steam reheating The user can select whether he wants to have steam reheating or not In case of having steam reheating item 2 has to be greater than or equal 2 4 Supplementary firing of exhaust Before the gas turbine exhaust or ambient air enters the HRSG it is possible to increase the temperature To be able to enter the SUPPLEMENTARY FIRING menu this item must be YES 5 Supercritical steam pressure POWSIM is able to calculate pressure level 1 with supercritical steam pressure greater than 221 bar 6 Ambient air temperature This temperature is used for exergy calculations and has an important meaning for calculation of stack loss 7 Ambient water temperature This temperature is used for exergy calculations and has an important meaning for calculation of condenser losses The user should be aware that if different values for item 6 and 7 are used there will be a discrepancy between the steam cycle exergy efficiency and the steam cycle exergy losses However using the actual ambient air temperature for i
7. 7 Maximum steam temperature If the exhaust gas temperature at the hot end of the HRSG is very high for example when using supplementary firing this item can be used to set an upper limit for the steam temperature at the hot end of the superheater This item may supersede item 5 8 Supercritical stage pressure loss The pressure loss can be given as a percentage negative number of the live steam pressure item 3 or as an absolute value positive number 9 10 Not used 11 Heat transfer coefficient for supercritical stage The heat transfer coefficient is used for the heat transfer area calculation HEAT RECOVERY STEAM GENERATOR Fag 64167 ITEV 02 23 9408 55 RESSURE LEVEL NUMBER 2 EHEAT PRESSURE LEVEL EAT LIVE STEAM PRESSURE t 40 000 ER HOT END TEMPERATURE DIFFERI 30 000 REHEAT STEAM TEMPERATURE i 560 000 ER PRESSURE LOSS 5 000 1 2 3 4 5 6 7 8 EAT TRANSFER COEFFICI HRSG input menu for reheat pressure level 1 Same as above 2 Reheat pressure level This the description of the type of the pressure level for which inputs are given in this menu 3 Reheat live steam pressure The steam pressure at the reheater exit hot end 4 Not used 5 Reheater hot end temperature difference The temperature difference between exhaust gas and steam at the hot end of the reheater 6 Not used 7 Maximum reheat steam temperature If the exhaus
8. ITE 02 23 9408 51 RESSURE LEVEL NUMBER ON RE PRESSURE LEVEL IVE STE PRESSURE INCH TEMPERATURE DIFFERENCE UPERH HOT END TEMPERATURE DIFFER PROACH TEMPERATURE DIFFER IMU E TEMPERATURE UPERH RESSURE LOSS RESSURE LOSS tbar RESSURE LOSS tbar EAT TRANSFER COEFFICIENT EAT TRANSFER COEFFICIENT EAT TRANSFER COEFFICIENT 1 2 3 4 5 6 7 8 HRSG input menu for subcritical pressure level pressure level number equal 1 1 Pressure level number This is the pressure level number for which inputs are given in this menu This item is for information only and cannot be changed by selecting the item 2 Non reheat pressure level This the description of the type of the pressure level for which inputs are given in this menu 3 Live steam pressure The steam pressure at the superheater exit hot end When selecting a pressure close up to the supercritical pressure make sure that the pressure losses item 8 11 does not result in a supercritical drum pressure 4 Pinch point temperature difference The difference between the exhaust gas temperature and the drum temperature 5 Superheater hot end temperature difference The temperature difference between exhaust gas and steam at the hot end of the superheater 6 Economizer approach temperature difference The difference between the drum temperature and the temperature of t
9. In some cases the low pressure turbine steam exit quality may be to low and cause erosion To avoid this problem water drainage devices may be used POWSIM is able to calculate with up to three water extractions POWSIM 1 2 2000 01 03 39 9 Isentropic efficiency The low pressure turbine expansion path is broken into steps and the efficiency is corrected for moisture when the exit quality is below that for the onset of condensation Wilson line The efficiency given for this item is corrected for moisture with the following relation Nis 7 1 7 Xmean 3 where Oi expansion step isentropic efficiency isentropic efficiency for section item 9 Xmean mean steam quality for the expansion step efficiency moisture correction factor 10 Mechanical and generator efficiency This item is the mechanical efficiency for the steam turbine multiplied with the generator efficiency 11 Steam turbine auxiliary power fraction Power demand for steam turbine oil coolers and controls 12 Transformer efficiency The electricity generated by the generator is usually transformed at the site of the power plant In order to include the transformer losses in the calculation of the plant net efficiency item 12 can be set to a value below 100 46 A typical value is 99 5 POWSIM 1 2 2000 01 03 40 3 6 4 Pumps The look of the PUMP menu depends on the number of pressure levels and whether reheating is specif
10. preheater exit hot end temperature Typical values are 7 10 EC 3 Pressure loss feedwater preheater 4 Heat transfer coefficient for preheater The heat transfer coefficient is used for the heat transfer area calculation 5 Pressure loss between flash tank feedwater tank The steam needed for deaeration in the feedwater tank is supplied from a flash tank which is connected to the exit of the low pressure economizer The steam that is flashed off is led through a pipe to the feedwater tank and with this item the pressure loss in this pipe can be given 6 Minimum feedwater temperature entering HRSG If the temperature of the water entering the feedwater preheater is close to or below the exhaust gas dew point some condensation of the exhaust gas water vapour may occur at the tube surfaces and cause corrosion To avoid this phenomena the feedwater should be heated up to a temperature well above the exhaust gas dew point before any heat exchange with the exhaust gas The feedwater coming from the condenser is heated up by mixing with the liquid fraction coming from the flash tank If the temperature after this mixing is below the value specified for this item the water from the feedwater preheater exit hot end is circulated to the feedwater preheater entrance cold end It is recommended to use a value of 60 EC If this value is close to the stack temperature the feedwater preheater heat transfer area becomes very large If no preheating of t
11. respect to plant net efficiency If supplementary firing is used the temperature after the supplementary firing can be optimized with respect to plant net efficiency The box below shows the input sequence for the optimization In the box on page 43 is an example of the input sequence shown The optimization procedure is a search through a number of combinations of the parameters which the net efficiency is maximized for For each parameter live steam pressures and supplementary firing temperature if used the user must give a range lower to upper value and a step value If the user want to use a constant value for a parameter this is simply accomplished by setting the lower value equal to the upper value POWSIM does not accept a lower value that is higher than the upper value or a step value that is higher than the difference between the lower and upper value except if upper and lower values are equal The number of cycle calculations is in some cases very high and the optimization procedure then requires long time It is however possible to break the optimiztion procedure by pressing B POWSIM remembers the values of the optimized parameters achieved when breaking the optimization procedure POWSIM 1 2 2000 01 03 42 USER ID 09 05 90 20 26 IZATION OF LIVE STEAM PRESSURES AND SUPPLEMENTARY FIRING ER OF PRESSURE LEVELS 3 R UPPER STEP FOR PRESSURE 1 EL 1 110 120 2 lt cr gt UPPER STEP FOR PRESSURE 1 EL 2 30 50
12. steam cycle data are checked for consistency and errors The user cannot leave this menu unless POWSIM accepts the input data If any changes in the steam cycle configuration have been made STEAM CYCLE CONFIGURATION menu the user should go through the items in this menu STEAM CYCLE INPUT Fag 64167 ITEV 02 23 9408 50 PUT ERY STEAM GENERATOR TEM FEEDWATER TANK CONDENSER FILE IN MEMORY E STEAM CYCLE DATA FROM FILE EAM CYCLE DATA ON FILE DRIVE DIRECTORY D POWSIM WORK TURBINE INPUT HomB ucdmswult 1 2 3 4 5 6 7 8 9 0 QAnDVIH UE nd 1 Full input The user is brought automaticly through all the menues for the steam cycle input This is useful when giving input for a new case Selecting this item is strongly recommended if the number of pressure levels is changed from the previous run 2 HRSG The menu for input of HRSG data is invoked 3 Preheating system and condenser The menu for input of data for the preheating system and condenser is invoked 4 Steam turbine The menu for input of steam turbine data is invoked 5 Pumps The menu for input of data for the pumps in the steam cycle is invoked 6 The name of the present steam cycle data file This item is for information only and cannot be changed by selecting the item If no steam cycle data file is retrieved or saved the name field is filled with dots 7 Retrieve steam cycle data from file When selecting this
13. 0 POWSIM 1 2 2000 01 03 2 DEAERATOR a RATOR i v FLASHTANK LP STEAM STEAM TURBINE x HEAT RECOVERY STEAM GENE HP STEAM Figure 5 Flowsheet diagram for the dual pressure steam cycle CONDENSER 600 TEMPERATURE C 550 500 450 400 350 300 250 200 150 100 50 0 75 150 225 300 375 450 525 600 675 750 HEAT TRANSFER MW Figure 6 TQ diagram for the dual pressure steam cycle POWSIM 1 2 2000 01 03 3600 3500 3400 3300 3200 3100 3000 2900 2800 2700 2600 2500 2400 2300 2200 2100 2000 Figure 7 ENTHALPY KJ KG 5 000 5 250 5 500 5 750 6 000 6 250 6 500 6 750 7 000 7 250 7 500 7 750 8 000 ENTROPY KJ KG K HS diagram for the dual pressure steam cycle POWSIM 1 2 2000 01 03 Z DEAERATOR f D Y FLASHTANK LP STEAM STEAM TURBINE HEAT RECOVERY STEAM GEN i CONDENSER gt Figure 8 Flowsheet diagram for the dual pressure reheat steam cycle TEMPERATURE C 600 550 500 450 400 350 300 250 200 150 100 X 50 0 75 150 225 300 375 450 525 600 675 750 HEAT TRANSFER MW Figure 9 TQ diagram for the dual pressure reheat steam cycle POWSIM 1 2 2000 01 03 3600 3500 3400 3300 3200 3100 3000 2900 2800 2700 2600 2500 2400 2300 220
14. 0 2100 5 000 5 250 5 500 5 750 6 000 6 250 6 500 6 750 7 000 7 250 7 500 7 750 8 000 Figure 10 ENTHALPY KJ KG ENTROPY KJ KG K HS diagram for the dual pressure reheat steam cycle POWSIM 1 2 2000 01 03 f N Y FLASHTANK LP STEAM HEAT RECOVERY STEAM GENERATOR STEAM TURBINE m gt Figure 11 Flowsheet diagram for the dual pressure supercritical reheat steam cycle 600 TEMPERATURE C 550 500 450 SS 400 350 300 250 200 150 100 50 0 75 150 225 300 375 450 525 600 675 750 HEAT TRANSFER MW Figure 12 TQ diagram for the dual pressure supercritical reheat steam cycle POWSIM 1 2 2000 01 03 3600 3500 3400 3300 3200 3100 3000 2900 2800 2700 2600 2500 2400 2300 2200 2100 2000 Figure 13 ENTHALPY KJ KG ENTROPY KJ KG K HS diagram for the dual pressure supercritical reheat steam cycle 5 000 5 250 5 500 5 750 6 000 6 250 6 500 6 750 7 000 7 250 7 500 7 750 8 000 POWSIM 1 2 2000 01 03 Z a7 DEAERATOR S z gt lt E 77 04 DRUM d e7 N LP STEAM IP STEAM STEAM TURBINE lt HP STEAM 7 CONDENSER HEAT RECOVERY STEAM GENERATOR Figure 14 Flowsheet diagram for the triple pressure steam cycle 600 TEMPERATURE C 550 500 450 400 350 300 250 N 200 CONS 150 10
15. 0 50 0 75 150 225 300 375 450 525 600 675 750 HEAT TRANSFER MW Figure 15 TQ diagram for the triple pressure steam cycle POWSIM 1 2 2000 01 03 3600 3500 3400 3300 3200 3100 3000 2900 2800 2700 2600 2500 2400 2300 2200 2100 2000 5 000 5 Figure 16 ENTHALPY KJ KG ENTROPY KJ KG K HS diagram for the dual triple pressure steam cycle 250 5 500 5 750 6 000 6 250 6 500 6 750 7 000 7 250 7 500 7 750 8 000 POWSIM 1 2 2000 01 03 LP STEAM IP STEAM O lt 2 lt LL Uu gt gt Q O lt STEAM TURBINE CONDENSER Figure 17 Flowsheet diagram for the triple pressure reheat steam cycle 600 TEMPERATURE C 550 500 450 400 350 S 300 N 250 N 200 150 100 50 0 75 150 225 300 375 450 525 600 675 750 HEAT TRANSFER MW Figure 18 TQ diagram for the triple pressure reheat steam cycle POWSIM 1 2 2000 01 03 3600 3500 3400 3300 3200 3100 3000 2900 2800 2700 2600 2500 2400 2300 2200 2100 2000 5 000 5 25 Figure 19 ENTHALPY KJ KG 0 5 500 5 750 6 000 6 250 6 500 6 750 7 000 7 250 7 500 7 750 8 000 ENTROPY KJ KG K HS diagram for the triple pressure reheat steam cycle 20 POWSIM 1 2 2000 01 03 LP STEAM IP STEAM o HL lt fc 2 oO lt
16. 2 23 9408 28 LOGICAL INPUT SEQUENCE GAS TURBINE INPUT SUPPLEMENTARY FIRING STEAM CYCLE CONFIGURATION STEAM CYCLE INPUT CALCULATION amp OUTPUT TERMISKE KRAFTSTASJONER VCREN 1995 POWSIM INFORMATION CHANGE DRIVE DIRECTORY D POWSIM WORK COLOUR SETUP QUIT THE PROGRAM 1 2 3 4 5 6 7 8 9 LO 11 12 13 14 15 16 17 18 19 1 Selecting this item results POWSIM to choose logical input sequence by invoking menues user has to go through in order to do a cycle calculation It is recommended to novel users of POWSIM to select this item to learn the proper sequence of input menues 2 Invokes the GAS TURBINE INPUT and GAS TURBINE CHECK menues 3 Invokes the SUPPLEMENTARY FIRING menu The gas turbine input data must be given before POWSIM accept this selection 4 Invokes the STEAM CYCLE CONFIGURATION menu The gas turbine input data must be given before POWSIM accept this selection 5 Invokes the STEAM CYCLE INPUT menu Input data for the gas turbine and steam cycle configuration must be given before POWSIM accept this item to be chosen If input data for the steam cycle configuration is not given before selecting this item POWSIM invokes the STEAM CYCLE CONFIGURATION menu first and goes directly to the STEAM CYCLE INPUT menu 6 By selecting this item the CALCULATION amp OUTPUT menu is invoked Input data for the gas turbine and steam cycle must be given before POWSIM accept this i
17. IN LIVE STEAM PIPE TO TURBINE RESSURE DROP IN REHEAT RETURN STEAM PIPE STEAM FRACTION THROUGH SEALS ISENTROPIC EFFICIENCY Steam turbine input menu for reheat pressure level pressure level number equal 2 1 3 Same as above 4 Pressure loss in reheat return steam pipe After expansion through the high pressure section pressure level 1 of the steam turbine the steam is led through a pipe to the HRSG for reheating The pressure loss is a percentage of the high pressure section exit pressure 5 Same as above 6 8 Not used 9 Same as above STEAM TURBINE INPUT Fag 64167 ITEV 02 23 94 08 58 RESSURE LEVEI UMBER 3 EAT LOSS FRO IVE STEAM PIPE TO TURBIN 1 000 RESSURE LOSS IN LIVE STEAM PIPE TO TURBINE 7 000 E FRACTION THROUGH SEALS 0 200 Al DENSER PRESSURE 0 040 V B T ON EA UM ING LOSS 30 000 ER OF LP TURBINE WATER EXTRACTIONS 3 SENTROPIC EFFICIENCY ECHANICAL AND GENERATOR EFFICIENCY 206 TEAM TURBINE AUXILIARY POWER FRACTION 5 250 RANSFORMER EFFICIENCY 500 Steam turbine menu for low pressure turbine 1 3 Same as above 4 Not used 5 Same as above 6 Condenser pressure This is the back pressure of the low pressure turbine 7 Leaving loss The exit velocities from a low pressure turbine may be quite high This item can be used to account for this loss 8 Number of LP turbine water extractions
18. POWSIM THE USER MANUAL FOR VERSION 1 2 WRITTEN BY OLAV BOLLAND January 3 2000 NTH Thermal Energy and Hydropower CONTENTS 1 GENERAL INFORMATION _ 1 1 About POWSIM yay UB WW CJ CJ 3 6 2 Preheating system and condenser 37 BU Stean 38 POWSIM 1 2 2000 01 03 1 GENERAL INFORMATION 1 1 About POWSIM POWSIM is a computer program for design calculations of steam cycles utilizing hot gas as heat source Data for a topping gas turbine cycle can be specified in order to calculate combined cycle performance POWSIM is developed by Dr ing Olav Bolland at the Norwegian University of Science and Technology 1 2 Computer requirements POWSIM is supplied as an executable DOS code and runs on IBM PC XT AT PS 2 or compatible with 640 K memory A math coprosessor on 286 386 systems is strongly recommended By the way this was written in 1991 If you still have a 286 386 it is about time you get a new PC A hard disk or a network drive or a 1 44 1 2 Mb floppy disk is required 1 3 Installation The POWSIM menu system requires that the following For WIN95 In the file c config sys the following line must be inserted DEVICE C WINDOWS COMMANDI ANSLSYS Check whether the file ANSI SYS exists on the directory given above For WIN NT In the file c winnt system32 autoexec nt the following lines must be inserted mode con codepage select 850 keyb no c winnt system32 keyboard sys In the file c winnt
19. ULTS TO FILE BALANCE amp EXERGY ANALYSIS ON SCREEN BALANCE amp EXERGY ANALYSIS TO FILE K IF SUPL FIRING INCREASES EFFICIENCY E HRSG TQ DIAGRAM PLOTTER FILE HP GL HRSG TQ DIAGRAM ON SCREEN HRSG TQ DIAGRAM ON SCREEN MANUAL INPUT E Hs DIAGRAM PLOTTER FILE HP GL Hs DIAGRAM ON SCREEN Hs DIAGRAM ON SCREEN MANUAL INPUT GAS PROPERTY TABLE GAS TURBINE INPUT STEAM CYCLE INPUT ROONROORKH mpm 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 Calculation and output menu In order to select items 5 15 the cycle must be calculated However it is possible to choose items 5 16 without first having used item 1 or 2 If the cycle is not calculated POWSIM does this before the action for items 5 15 is performed 1 Calculate cycle The cycle is normally calculated within 0 3 5 seconds and the results are shown The results can also be viewed on the screen by selecting item 5 2 Calculate cycle amp heat transfer area This is the same as item 1 but in addition the heat transfer area for the different HRSG sections are calculated The calculation of the HRSG heat transfer area take some more time than the cycle calculation The reason for this is that the different HRSG sections are calculated in small steps in order to take into the influence of variable cp of the fluids 3 Optimize cycle The live steam pressures for the different HRSG sections can be optimized with
20. anged most efficiently from within POWSIM see sections 0 and 0 3 Files with the extension PDT are input files containing the user supplied steam cycle input data The content of a PDT file may be changed with an editor but this is not recommended The information in this file is changed most efficiently from within POWSIM see sections 0 and 0 4 Files with the extension RES contain the computational results from a POWSIM calculation This is a sequential ASCII file and can be printed out by any type of printer This file may be included in any word processing system which is able to read ASCII files any decent word processing system does that See section 0 5 Files with the extension XRY contain the computational results from the exergy analysis from a POWSIM calculation This is a sequential ASCII file and can be printed out on any type of printer This file may be included in any word processing system which is able to read ASCII files see section 0 6 Files with extension HPT are plotter files with the heat recovery TQ diagram This a file with a HP GL plotter format and can be plotted directly on any plotter accepting this format Some laser printers accept this file format This file may also be included in some word processing systems see section 0 7 Files with extension HPH are plotter files with the steam cycle HS diagram This a file of the same type as described above see section 0 8 F
21. ary firing is chosen in the STEAM CYCLE CONFIGURATION menu 3 8 Screen colours By selecting item 18 in the POWSIM MAIN MENU the user can change foreground and background colour for the screen In Table 3 are recommendations given for combinations of foreground and background colours When ending a POWSIM session the last selection of screen colours are saved on the POWSIM DEF file in order to have the last chosen screen colours for the next run of POWSIM The user is not allowed to select same foreground and background colour and if so an error message is displayed For LCD screens use foreground 2 and background 18 or vice versa REEN COLOURS Fag 64167 ITEV 02 23 9409 14 9 FOREGROUND PRESENT CHOICE 9 LAC E Dd zj D Q H BACKGROUND PRESENT CHOICE 12 LAC ED REE ELLOW LUE WHITE SWITCH FOREGROUND AND BACKGROUND COLOUR WKODAWRrRAO 120 O1 iS CO PD S 2 9 These items each represents a foreground colour The colours are black 2 red 3 green 4 yellow 5 blue 6 magenta 7 cyan 8 and white 9 11 18 These items each represents a background colour The colours are black 11 red 12 green 13 yellow 14 blue 15 magenta 16 cyan 17 and white 18 19 Switch between foreground and background colours POWSIM 1 2 2000 01 03 45 Table 3 C
22. ave the gas turbine input data on file When selecting this item the screen is cleared and a two column list of gas turbine data files PGT are displayed if any exist The user is asked for a file name The file name must be given without the file extension After typing the file name the user is asked to confirm his choice by pressing Y POWSIM then saves the file and gives a message if it was not successful An example of saving a gas turbine data file is given below Directory List of C POWSIM PGT 1 V94 PGT GI PGI TURBINE2 PGT ABB13E PGT GT1 PGT GEFR9E PGT V64 PGT PRESENT FILE IN MEMORY IS GEFR9E PGT TO BE SAVED NO EXTENSION TURBINE1 lt cr gt TURBINE1 PGT CONFIRM Y N Y Saving the gas turbine input data bold characters are user supplied input 3 Return to the GAS TURBINE INPUT menu 10 The gas turbine net efficiency Based on the given inputs for the gas turbine the net efficiency is calculated The following equation is applied to calculate this efficiency Por Pax mf LHV d Ocr gas turbine net efficiency item 10 Por gas turbine gross power output item 6 Paux gas turbine auxiliary power requirement item 8 gas turbine fuel mass flow item 7 LHV fuel lower heating value item 9 POWSIM 1 2 2000 01 03 28 18 Exhaust gas molecular weight 19 Gas constant 20 Change drive and directory See explanation in sec
23. e extension HPT to the user supplied file name The user is also asked to do any changes in the default values for the axis text the heading and the scaling of the axis The plot may be viewed on the screen before printing it to file 11 Plot the heat recovery TQ diagram on screen The TQ diagram is displayed on the screen and POWSIM is using default values for axis text and heading and the axis are scaled automaticly 12 Plot the heat recovery TQ diagram on screen manual input This is the same as described for item 11 except that the user is user asked to do changes in the default values as described for item 10 13 Make the steam cycle HS diagram enthalpy entropy plotter file HP GL The HS diagram for the steam cycle is written to a file with the HP GL format The user is asked for a file name no extension POWSIM adds the extension HPH to the user supplied file name The user is also asked to do any changes in the default values for the axis text the heading and the scaling of the enthalpy axis y axis The entropy axis x axis is fixed and cannot be chanced The user is also asked if he wants to change the number of lines 0 4 with constant steam quality in the two phase region and if the number of lines is greater than zero POWSIM asks for steam quality values for each line The plot may be viewed on the screen before printing it to file 14 Plot the steam cycle HS diagram on screen The HS diagram is displayed on the scree
24. er of configurations are allowed These are summarized in Table 2 Flowsheet diagrams and TQ diagrams for the valid configurations are shown on the following pages Supplementary firing using CH of the heat source gas may be gas turbine exhaust or any other composition can be applied A pressure level is here defined as a heat recovery boiler section with economiser evaporator and superheater POWSIM is regarding reheating as a pressure level A dual pressure steam cycle with reheating is in POWSIM a cycle with 3 pressure levels though steam generation takes place at 2 pressure levels Table 2 Steam cycle configurations NUMBER OF STEAM SUPERCRITICAL PRESSURE LEVELS REHEATING STEAM PRESSURE POWSIM 1 2 2000 01 03 HEAT RECOVERY STEAM GENERATOR Figure 2 600 550 500 450 400 350 300 250 200 150 100 50 Figure 3 FLASHTANK LIVE STEAM Flowsheet diagram for the single pressure steam cycle TEMPERATURE C STEAM TURBINE 50 100 150 200 250 300 HEAT TRANSFER MW TQ diagram for the single pressure steam cycle 450 500 POWSIM 1 2 2000 01 03 3600 3500 3400 3300 3200 3100 3000 2900 2800 2700 2600 2500 2400 2300 2200 2100 2000 5 Figure 4 ENTHALPY KJ KG ENTROPY KJ KG K HS diagram for the single pressure steam cycle 000 5 250 5 500 5 750 6 000 6 250 6 500 6 750 7 000 7 250 7 500 7 750 8 00
25. he cycle calculation 4 Not used 5 10 Exhaust gas composition mole fractions and molecular weight before supplementary firing These items are in this menu only for information and cannot be changed by the user These values can be changed in the GAS TURBINE INPUT menu 11 Not used 12 17 Exhaust gas composition mole fractions and molecular weight after supplementary firing These items are updated when choosing item 3 18 Supplementary firing fuel flow This is the amount of fuel that is necessary to increase the temperature of the exhaust gas from the value for item 1 to the value for item 2 POWSIM 1 2 2000 01 03 30 3 5 Steam cycle configuration This menu is used to select the type of steam cycle system If an invalid configuration is specified an error message appears in the lower left corner of the screen and POWSIM does not allow the user to leave the menu STEAM CYCLE CONFIGURATIO Fag 64167 ITEV 02 23 9408 49 BOTTOMING CYCLE UM NUMBER OF PRESSURE LEVELS ER OF PRESSURE LEVELS REHEATING LEMENTARY FIRING OF GAS TURBINE EXHAUST YES RCRITICAL STEAM PRESSURE NO ENT AIR TEMPERATURE for exergy analysis 15 000 ENT WATER TEMPERATURE for exergy analysis 15 000 NAME maximum 12 characters 2 TRYKK 1 2 3 4 5 6 7 8 MHHe UU gc EAD STEAM CYCLE DATA FROM FILE CHANGE DRIVE DIRECTORY D POWSIM WORK 1 Maximum number of pressure levels For POWSIM version 1
26. he feedwater is wanted the value for this item should be set to a very low number for example 0 EC 7 Cooling water entering temperature The temperature of the cooling water entering the condenser 8 Cooling water temperature rise The temperature rise of the cooling water through the condenser 9 Total cooling water pressure loss In order to calculate the cooling water pump work the user may specify the cooling water pressure loss in the condenser and in the cooling water ducts POWSIM 1 2 2000 01 03 37 3 6 3 Steam turbine The steam turbine expansion path is broken into a number of sections which correspond to the number of HRSG pressure levels The steam turbine input sequence consists of a number of menues corresponding the number of pressure levels There are three types of menues though these are quite similar The different menues are menu for non reheat pressure level except for low pressure turbine menu for reheat pressure level pressure level number equal 2 F menuforlow pressure turbine STEAM TURBINE INPUT Fag 64167 ITEV 02 23 94 08 58 PRESSURE LEVEL NUMBER 1 HEAT LOSS FROM LIVE STEAM PIPE TO TURBIN 1 000 C X PRESSURE LOSS IN LIVE STEAM PIPE TO TURBINE 5 000 STEAM FRACTION THROUGH SEALS 0 300 1 2 3 4 5 6 7 8 9 ISENTROPIC EFFICIENCY Steam turbine input menu for non reheat pressure level except for low pressure turbine 1 Pressure level number Thi
27. he water at the economizer exit hot end 7 Maximum steam temperature If the exhaust gas temperature at the hot end of the HRSG is very high for example when using supplementary firing this item can be used to set an upper limit for the steam temperature at the hot end of the superheater This item may supersede item 5 8 10 Pressure loss for superheater evaporator and economizer The pressure loss can be given as a percentage negative number of the live steam pressure item 3 or as an absolute value positive number 11 13 Heat transfer coefficient for superheater evaporator and economizer The heat transfer coefficients are used for the heat transfer area calculation POWSIM 1 2 2000 01 03 34 1 6 Same as above HEAT RECOVERY STEAM GENERATOR Fag 64167 1 02 23 9408 54 RESSURE LEVEL NUMBER ON REHEAT PRESSURE LEVEL IVE STEAM PRESSURE INCH POINT TEMPERATURE DIFFERENCE PERHEATER HOT END TEMPERATURE DIFFER ONOMIZER APPROACH TEMPERATURE DIFFER AnUr zU C 1 2 3 4 5 6 7 8 PERHEATER PRESSURE LOSS APORATOR PRESSURE LOSS tbar ONOMIZER PRESSURE LOSS tpar H H oe lt EAT TRANSFER COEFFICIENT APORATER EAT TRANSFER COEFFICIENT ONOMIZER HEAT TRANSFER COEFFICIENT MBER OF EVAPORATOR CIRCULATIONS M Cn lt iu lt HRSG input menu for s
28. ied or not Menu items with odd numbers are for isentropic efficiency and even numbers are for mechanical efficiency In the text for the menu items for feedwater pumps there is a number 1 2 and so on These numbers refer to the HRSG pressure levels A reheat pressure level has no pumps and POWSIM does not ask for input for any pumps for such a pressure level see example below There are no input items for the evaporator circulation pumps but POWSIM use the efficiencies given for the feedwater pumps for the calculation of the circulation pumps Fag 64167 IT 02 23 9409 07 ISENTRO ISENTRO ISENTRO SENTRO EEDWATER PU EEDWATER PU EEDWATER PU EEDWATER PU EEDWATER PU FEEDWATER PU CONDENSATE P ECHAN CONDENSATE P SENTROPI COOLING WATE ECHANICAI COOLING WATE vQUvVAWTANWAT Pumps input menu Odd numbers Isentropic efficiency for feedwater pumps which is also the efficiency for the circulation pumps condensate pump and cooling water pump Even numbers Mechanical efficiency for feedwater pumps which is also the efficiency for the circulation pumps condensate pump and cooling water pump POWSIM 1 2 2000 01 03 41 3 7 Calculation amp output ULATION amp OUTPUT Fag 64167 ITEV 02 23 9409 11 ULATE CYCLE ULATE CYCLE amp HEAT TRANSFER AREA PUTATIONAL RESULTS ON SCREEN TATIONAL RES
29. iles with extension PRO are gas property table files for a given gas composition This file may be useful when gas properties are required for hand calculations see page 44 9 The POWSIM LOG file contains information about the frequency of using POWSIM Each time the user runs POWSIM a new line of text is added to the file A text line contains information about POWSIM version number date and time This file may be deleted by the user without any concern 10 The POWSIM DEF file contains information about colour selection from the previous run of POWSIM When the user has selected foreground and background colours which he is comfortable with these colours are used in the next POWSIM runs This file also contains the name of the input files that were used when ending the last POWSIM run When starting POWSIM these input files are automaticly retrieved in order to enable the user to continue from the same state with respect to input values as from the last POWSIM run The POWSIM DEF file must be present If this file is deleted POWSIM is unable to run 11 The HS SAT file contain the saturation line given as a number of entropy enthalpy values The file is read by POWSIM when plotting the steam cycle HS diagram see page 44 1 5 How to work with the menues POWSIM 1 2 2000 01 03 A menu consists of a number of item lines On the left edge of each line there is an item number When entering a menu the cursor appears near the b
30. item the screen is cleared and a three column list of steam cycle data files PDT are displayed if any exist The user is asked for a file name The file name must be given without the file extension After typing the file name the user is asked to confirm his choice by pressing Y POWSIM then reads the file and gives a message if it was not successful 8 Save steam cycle data on file When selecting this item the screen is cleared and a three column list of steam cycle data files PDT are displayed if any exist The user is asked for a file name The file name must be given without the file extension After typing the file name the user is asked to confirm his choice by pressing Y POWSIM then saves the file and gives a message if it was not successful 9 Change drive and directory See explanation in section 3 1 for item 17 page 25 10 Invokes the GAS TURBINE INPUT and GAS TURBINE CHECK menues POWSIM 1 2 2000 01 03 33 3 6 1 Heat recovery steam generator The HRSG input sequence consists of a number of menues corresponding the number of pressure levels There are four types of menues though these are quite similar The different menues are menu for subcritical pressure level pressure level number equal 1 menu for subcritical pressure level pressure level number greater than 1 menu for supercritical pressure level 414111 menu for reheat pressure level HEAT RECOVERY STEAM GENERATOR Fag 64167
31. n and POWSIM is using default values for axis text and heading and the axis are scaled automaticly 15 Plot the steam cycle HS diagram on screen manual input This is the same as described for item 14 except that the user is user asked to do changes in the default values as described for item 13 16 Make gas property gas table which is written to a file The properties are also printed on the screen The properties are written in columns and the columns are temperature EC local cp MH MT p kJ kg K integrated cp OH T KJ kg K enthalpy kJ kg internal energy kJ kg entropy kJ kg K and isentropic exponent POWSIM prompts for a file name without extension and adds the extension PRO The user is asked for a zero point temperature starting and ending temperature for the table and temperature step The zero point temperature defined as the temperature at which the enthalpy the internal energy and the entropy equal zero At the beginning of the file the gas composition molecular weight and gas constant is written before the table starts The gas composition used for making this table is given in the GAS TURBINE INPUT menu see section 0 17 Gas turbine input The GAS TURBINE INPUT menu is invoked 18 Steam cycle input The STEAM CYCLE INPUT menu is invoked POWSIM 1 2 2000 01 03 44 19 Supplementary firing The SUPPLEMENTARY FIRING menu is invoked This menu line is visible only if supplement
32. ne data file is given below Directory List of C POWSIM PGT RBINE1 PGT V94 PGT GI PGT RBINE2 PGT ABB13E PGT GT1 PGT FR9E PGT V64 PGT ESENT FILE IN MEMORY IS GEFR9E PGT ILE TO BE RETRIEVED NO EXTENSION TURBINE1 cr ETRIEVE FILE TURBINE1 PGT CONFIRM Y N Retrieve a gas turbine data file bold characters are user supplied input 3 Not used 4 Name of gas turbine The number of characters in the gas turbine name is restricted to 12 5 All the input quantities given for the gas turbine is by POWSIM interpreted to be for one gas turbine If the user wants to calculate a steam cycle fed by exhaust gas from multiple gas turbines this item can be used instead of giving mass flow rates and power output for multiple gas turbines POWSIM 1 2 2000 01 03 26 6 Gas turbine gross power output referred to the generator terminals The gas turbine net power output is the value given for this item minus the auxiliary power consumption item 8 7 Fuel mass flow 8 Gas turbine auxiliary power requirement 9 Fuel lower heating value 10 Not used 11 Gas turbine exhaust mass flow 12 Gas turbine exhaust temperature 13 17 Exhaust gas composition mole fraction or volume fraction Input for five different gases are required nitrogen 13 argon 14 carbondioxide 15 oxygen 16 and water vapour 17 The oxygen fraction must always be larger than zero 18 Sum of the gas fraction
33. ny errors an error message is shown on the screen When leaving this menu without errors the GAS TURBINE CHECK menu is invoked directly GAS TURBINE INPUT Fag 64167 ITEV 02 23 94 08 37 PRESENT GAS TURBINE DATA FILE v94 pgt READ NEW GAS TURBIN D n TURBINE NAME Siemens V94 ER OF GAS TURBINI x 2 AS TURBINI POWE UTPUT 379044 000 UEL MASS 1 21 470 AS TURBINI LIA OWER REQUIREMENT 800 000 UEL LOWER TING VALUE 50056 000 QAZOQ H Q EXHAUST FLOW RATE 1130 460 EXHAUST TEMPERATURE 561 400 EXHAUST COMPOSITION NITROGEN 75 800 ARGON 0 000 CARBON DIOXIDE 3 100 100 WATER VAPOUR E SUM OF COMPONENTS 10 014 Q0 PO S N CHANGE DRIVE DIRECTORY D POWSIM WORK 1 The name of the present gas turbine data file This item is for information only and cannot be changed by selecting the item If no gas turbine file is retrieved or saved the name field is filled with dots 2 Retrieve a gas turbine data file When selecting this item the screen is cleared and a two column list of gas turbine data files PGT are displayed if any exist The user is asked for a file name The file name must be given without the file extension After typing the file name the user is asked to confirm his choice by pressing Y POWSIM then reads the file and gives a message if it was not successful An example of retrieving a gas turbi
34. olour selection POWSIM BACKGROUND COLOURS GOOD O ACCEPTABLE GOOD COLOUR NOT ALLOWED POWSIM 1 2 2000 01 03 46 POWSIM 1 2 2000 01 03 POWSIM 1 2 200
35. ottom on the right hand side of the screen the command prompt In front of the cursor there is a text SELECT ITEM gt The user may at this prompt type a command and the available commands are shown in Table 1 In the upper right corner of the screen there is a user identification date MM DD YY and time Table 1 Commands to be used in the menues COMMAND ABBREVIATION DESCRIPTION A window appears on the left hand side of the screen displaying available H commandis See text box below this table The screen is cleared and the menu is refreshed nr is the selected item number By typing a number and then pressing cr the cursor moves to the selected item line input item or an action is taken action item The cursor moves the first input item and the item value may be changed and or use A cr The cursor will then move to the next input item and so on STOP POWSIM tun is ended There are two types of items action items and input items The former type of item is used when a specific action is to be taken such as performing a calculation changing directory saving input data and so on The latter item type is used for changing an item value When the cursor is located on an item line the cursor can be moved to the command prompt SELECT ITEM gt by typing QUIT lt cr gt or lt cr gt There are three ways to end a POWSIM run without turning the computer off and these are
36. s given in items 13 17 This item is for information only and cannot be changed by selecting the item The sum of the component fractions has to be 100 An error message is displayed if the sum of components does not equal 100 19 Not used 20 Change drive and directory See explanation in section 3 1 for item 17 page 25 POWSIM 1 2 2000 01 03 27 3 3 Gas turbine check This menu looks very much like the GAS TURBINE INPUT menu When leaving the GAS TURBINE INPUT menu this menu is invoked directly In the following only the differences from the GAS TURBINE INPUT menu are explained Only items 2 3 and 20 can be selected from this menu RBINE CHECK Fag 64167 ITEV 02 23 9408 37 ENT GAS TURBINE DATA FILE v94 pgt GAS TURBINE DATA ON FILE RN TO GAS TURBINE DATA INPUT MENU TURBINE NAME Siemens V94 ER OF GAS TURBINES 2 AS TURBINI POWER OUTPUT 379044 000 UEL MASS 21 470 AS TURBINI LIARY POWER REQUIREMENT 800 000 UEL LOWER TING VALUE 50056 000 GAS TURBINI EFFICIENCY CALCULATED 35 195 EXHAUST FLOW RATE 1130 460 EXHAUST TEMPERATURE 561 400 EXHAUST COMPOSITION NITROGEN 75 800 ARGON 0 000 CARBON DIOXIDE 3 100 OXYGEN 14 100 WATER VAPOUR 7 000 EXHAUST GAS MOLECULAR WEIGHT 28 374 kg kmole GAS CONSTANT 038 kJ kg K CHANGE DRIVE DIRECTORY D POWSIM WORK oO zou gy G CO 0r OO i000 10 01 iS C0 PD S N 2 S
37. s is the pressure level number for which inputs are given in this menu This item is for information only and cannot be changed by selecting the item 2 Heat loss from live steam pipe to turbine This is the heat loss from the superheater exit to the steam turbine inlet It should be noted that if a pressure loss is specified in item 3 there will be a temperature drop between the HRSG and steam turbine regardless of the heat loss This is due to the fact that the Joule Thompson coefficient is greater than zero for the steam conditions that are typical in this respect The Joule Thompson coefficient is defined by the relation a Eq 2 h where T temperature pressure h enthalpy 3 Pressure loss in live steam pipe to turbine The pressure loss in the pipe going from the HRSG to the steam turbine The item value is the pressure loss in percent of the pressure at the superheater exit hot end 4 Not used 5 Steam fraction through seals The fraction of the steam fed to the steam turbine that is lost through the seals This fraction is therefore not expanded through the turbine and does not contribute to the steam turbine work 6 8 Not used 9 Isentropic efficiency Each section or pressure level is calculated by an individual isentropic efficiency POWSIM 1 2 2000 01 03 38 STEAM TURBINE INPUT Fag 64167 02 23 9408 58 RESSURE LEVEL NUMBER EAT LOSS FROM LIVE STEAM PIPE TURBIN C X RESSURE LOSS
38. system32 config nt the following line must be inserted device c winnt system32 ansi sys POWSIM may be run from a floppy disk but it is recommended to install it on a hard disk For installation on a hard disk the following procedure should be used Create a new directory this is not necessary if you are upgrading to a new version and a directory already exists The DOS command for creating a new directory is C gt MD POWSIM lt cr gt Then change the current directory by using the following command CD POWSIM cr Install POWSIM from the installation floppy disk by using the following command POWSIM 1 2 2000 01 03 C POWSIM gt COPY A cr or C POWSIM gt COPY cr If this procedure is successful POWSIM is now ready to be run Your prompt may not appear as the prompt underlined shown in the procedure above To run POWSIM use the command C POWSIM gt POWSIM lt cr gt POWSIM uses two types of input files see section 0 and one or both of these files may be written on the command line Below are some examples of how this is done Be sure to insert a space between the file names Both uppercase and lowercase may be applied but do not mix cases on the DOS command line when typing the file names When only one file is specified POWSIM uses the file from the last run for the unspecified file type One should be aware that POWSIM remember the name of the input files which were used in the last run
39. t gas temperature at the hot end of the HRSG is very high for example when using supplementary firing this item can be used to set an upper limit for the reheat steam temperature at the hot end of the reheater This item may supersede item 5 8 Reheater pressure loss The pressure loss can be given as a percentage negative number of the reheat steam pressure item 3 or as an absolute value positive number 9 10 Not used 11 Reheater heat transfer coefficient The heat transfer coefficient is used for the heat transfer area calculation POWSIM 1 2 2000 01 03 36 3 6 2 Preheating system and condenser PREHEATING SYSTEM AND CONDENSE Fag 64167 ITEV 02 23 9408 56 PRESSURE IN FEEDWATER TANK 1 200 bar FEEDWATER TANK APPROACH TEMPERATURE 10 000 C CX PRESSURE DROP PREHEATER 4 000 bar PREHEATER HEAT TRANSFER COEFFICIENT 50 000 W M2 K PRESSURE DROP BETWEE FLASH TANK FEEDWATER TANK 0 200 bar MINIMUM FEEDWATER TE ERATURE ENTERING HRSG 60 000 C X COOLING WATER ENTER TEMPERATURE 15 000 C X COOLING WATER TEMPE URE RISE 7 500 C X TOTAL COOLING WATER ESSURE DROP 10 000 M H20 1 2 3 4 5 6 7 8 9 1 Pressure in feedwater tank The pressure at which deaeration takes place It is recommended to use a value between 1 and 2 bar 2 Feedwater tank approach temperature The difference between the temperature in the feedwater tank and the feedwater
40. tem 6 and the actual cooling water temperature for item 7 give the best picture of the stack loss and condenser losses 8 Case name A case identifier restricted to 12 characters may be specified The case name will appear on plot diagrams and in the output files 9 Not used POWSIM 1 2 2000 01 03 31 10 Retrieve steam cycle data from file When selecting this item the screen is cleared and a two column list of steam cycle data files PDT are displayed if any exist The user is asked for a file name The file name must be given without the file extension After typing the file name the user is asked to confirm his choice by pressing Y POWSIM then reads the file and gives a message if it was not successful An example of retrieving a gas turbine data file is given below CYCLE1 PDT 3PRS PDT CYCLE2 PDT TEST PDT 2PR PDT 2P PDT PRESENT FILE IN MEMORY IS CYCLE1 PDT FILE TO BE RETRIEVED NO EXTENSION 2PR cr RETRIEVE FILE SLETT2 PDT CONFIRM Y N Retrieve a steam cycle data file bold characters are user supplied input 11 Change drive and directory See explanation in section 3 1 for item 17 page 25 POWSIM 1 2 2000 01 03 32 3 6 Steam cycle input The STEAM CYCLE INPUT menu is the top menu for user supplied steam cycle data Menues for different sections of the steam cycle can be invoked The steam cycle inputs can be saved or retrieved from this menu When leaving this menu the
41. tem to be chosen 7 15 Not used 16 Display information about POWSIM version number date of origin user identification and a telephone number and name to contact for help Statistics for the use of POWSIM are also displayed 17 Current directory and drive can be changed by selecting this item POWSIM is able to save retrieve files only to from the current directory and drive see page 25 18 Screen colours can be selected both foreground and background colours When ending a POWSIM run the last selection of screen colours are saved on the POWSIM DEF file in order to have the same screen colours for the next run of POWSIM POWSIM 1 2 2000 01 03 24 DRIVE sie DIRECTORY POWSIMNWORK D NPOWSIMNWORK cr ADMIN lt cr gt URRENT DRIVE or CURRENT DIRECTORY ADMIN PATHNAME C ADMIN Changing drive and directory bold characters are user supplied input 19 The user is prompted to confirm quitting POWSIM By responding with Y the program is stopped Any response other than Y will continue the POWSIM run Before selecting this item the user should ensure that the input data are saved on file Otherwise all input data are lost POWSIM 1 2 2000 01 03 25 3 2 Gas turbine input The gas turbine input data are checked for consistency when leaving the menu If there are errors in the input data the user is not allowed by POWSIM to leave the menu If there are a
42. tion 3 1 for item 17 page 25 POWSIM 1 2 2000 01 03 29 3 4 Supplementary firing The exhaust gas leaving the gas turbine s can be fired in order to increase the plant power output and in some cases also increase the efficiency Methane is used as fuel for this supplementary firing SUPPLEMENTARY FIRING Fag 64167 ITEV 02 23 9408 43 EXHAUST GAS TEMPERATURE BEHIND GAS TURBINE 561 400 C X SUPPLEMENTARY FIRING TEMPERATURE 650 000 C X CALCULATE SUPPLEMENTARY FIRING NITROGE before supplementary firing ARGO CARBONDIOXIDE OXYGEN WATER VAPOUR MOLECULAR WEIGHT n m o Q 52 z after supplementary firing ONDIOXIDE EN R VAPOUR CULAR WEIGHT A kg kmole LEMENTARY FIRING FUEL FLOW CH4 kg s ti ti Q U O 1 2 3 4 5 6 4 8 9 LO 11 12 13 14 L5 L6 L7 18 1 Exhaust gas temperature behind gas turbine This item is for information only and cannot be changed by user in this menu This value can be changed in the GAS TURBINE INPUT menu 2 Supplementary firing temperature This is the desired exhaust gas temperature after the firing The value for this item must be higher than the value for item 1 Otherwise no calculation of the supplementary firing is performed 3 Calculate supplementary firing It is not necessary to choose this item before leaving the menu The supplementary firing is calculated automaticly when doing t
43. ubcritical pressure level pressure level number greater than 1 7 Not used 8 13 Same as above 14 Number of evaporator circulations In the evaporator the circulated flow rate is larger than the steam quantity flow rate by a factor This menu item appears only for the highest pressure level number item 1 ECOVERY STEAM GENE Fag 64167 ITEV 02 23 9408 55 SURE LEVEL NUMBER RCRITICAL PRESSU LEVEL RCRITICAL STEAM PRESSURE gt 221 bar H POINT TEMPERATURE DIFFERENCE RCRITI L STAGE HOT END TEMP DIFFERENCE Haa UM STI TEMPERATURE RCRITI STAGE PRESSU LOSS C Ez E HEAT TRANSFER COEFFICIENT HRSG input menu for supercritical pressure level 1 Same as above 2 Supercritical pressure level This the description of the type of the pressure level for which inputs are given in this menu 3 Supercritical steam pressure The steam pressure at the exit of the supercritical stage hot end The pressure has to be greater than 221 bar 4 Pinch point temperature difference The smallest difference between the exhaust gas temperature and the supercritical steam except for the difference at the exit of the supercritical stage item 5 5 Supercritical stage hot end temp difference The temperature difference between exhaust gas and supercritical steam at the hot end of the supercritical stage 6 Not used POWSIM 1 2 2000 01 03 35

POWSIM

Contents

Download Pdf Manuals

Related Search

Related Contents