T W O P H A S E F L O W GENERAL INSTRUCTIONS The two phase flow program is designed to operate under MSDOS and will work with all IBM and Compatible PC's. The files on the disk called TWOPHASE.EXE, TWOPHASE.INP, and TWOPHASE.PIC work together and should be transferred to the same sub- directory of your Hard Disk. They are all part of the program. The .PIC file contain the screens used by the program, and the .INP file contains information for the screen generator. The .EXE file contains the program logic. The other files on the disk with the extension .TPH are example program. When you save a file it will be saved with this extension. The program is not copy protected, and can be installed onto your hard disk in the normal manner by copying all the files onto a sub directory of the hard disk. The program can be started by inserting the program disk into the A drive and giving the name of the program TWOPHASE. The title screen will come up and you will be asked if you wish to load an existing file or run a new problem. Input L to load a file or R to run a new case. If you select L then the two phase problems save on the disk will be shown on the screen. You can pick one by moving the cursor to the desired file and pressing the return key. The file will be loaded and the Main operating screen will come up. If you pressed R then this screen will come up with no input information loaded. The TWO PHASE program uses function key with a command line prompt, and input windows. The system is very user friendly and you will probably not require the use of these instructions to use the program. PROGRAM OPERATION The Two phase program input screen will be the normal operating environment for the program. You should start to operate by filling in the required information to size the lines. The first field is the title for the problem. You can use this field to identify the line by filling in the line number or case description. The pipe schedule can be selected by pressing the F2 key. The default schedule is Schedule 40 CS. If you press the F2 key a window will come up giving other choices. The schedule key allows you to automatically give the true internal diameter and pipe roughness for different standard pipes. These values can be over ridden by the main input screen if non- standard pipe is being used. Input the Nominal diameter in inches and the internal diameter and pipe roughness is calculated and is shown on the screen. The program will go to these fields so that you can override the values, if desired. To accept the computer generated values then press the return key. The Arrow keys that control the cursor will also move the cursor to various fields to permit selected input on desired fields. However, the return key must be pressed to input a new value. After the pipe information has been given, the data must be inputted to describe the fluids flowing through the pipe. The Liquid information is filled in first. Give the liquid flow rate in Lb/H, The Liquid Density in Lb/Ft3. The Liquid Viscosity in Centipoise, and the liquid Surface Tension in Dyne/Cm. Hydrocarbon systems have surface tension values of approximately 10 or less, Water has a surface tension of approximately 35. The Vapor flow information is filled in next. Give the flow rate in Lb/H, The vapor density in Lb/Ft3, and the Vapor Viscosity in centipoise. The vapor density can be calculated for the pipe conditions by pressing the F4 key. A window will come up that asks for the pressure in Psia, temperature in F, the MW of the gas and the Z or compressibility data. Fill out this information and press the F10 key and the vapor density will be calculated. For isothermal flow problems where critical flow is not exceeded, the average pressure between the inlet and outlet pressures can be used to give a accurate result. This may be a trial and error procedure that is made easily with this program. When all data is filled in, the program can be run by pressing the F10 key. If you do not press the F10 key then the input cursor will return to the first input field, the Case description and you can change the data. When the F10 key is pressed the program calculates the flow regime of the system by using the Baker Chart method. The program give the Baker chart coordinates X and Y as well as the flow regime. This data is described in the Methodology section of these instructions. The Lockhart and Martinelli method is used to calculate the two phase pressure drop, and is explained in the Methodology section. The method is based on a correlation of two phase pressure drop from the pressure drops and flow regimes of the liquid and vapor as if they were flowing independently through the pipe. Consequently the program calculates and presents the velocity, Reynolds Numbers, Friction Factors and PSI/100 feet for both the liquid and vapor phases. The Martinelli X^2 and Omega^2 are also presented. The two phase pressure drop is usually considerably higher than either the liquid or vapor phase pressure drop. The total line pressure drop can be calculated by hand by multiplying the pressure drop for two phase flow in Psi/100 ft by the total equivalent feet of the pipe system. This is the straight length of pipe plus the pressure drop consumed by fittings and bends ect. The effect of static head must also be calculated for vertical pipe rises. The equivalent feet of fitting, bends ect. is calculated by pressing the F3 key. A window will come up that allows you to enter the fitting description, When all the data is inputted then press the F10 key to calculate the total equivalent feet for the pipe diameter used in the Main Screen. For homogeneous flow regimes the hydrostatic head can be calculated by pressing the F5 key. This screen will also calculate criteria for erosion. The methodology section reviews these procedures. When calculating static head considerations for two phase flow, consider only the sum of the vertical rises. Do not deduct for descending flow since you do not get a reduction in the pressured drop for downflow with two phase systems. The F9 key will print a report of the two phase program to your printer. First press F9 and then press the return key when your printer is ready. The F8 key will save the problem to disk for future work. Press F8 and then F1 to save the file or F2 to load a new file from the disk. The program will prompt you through the disk operations from the command line. When saving a file you should give an eight letter name, but do not include a period or extension. The extension TPH is automatically added to the name by the program for data files. Press the ALT key and the Q key to quit the program. The command line will ask if you really want to quit. Answer with the Y key to exit. PROGRAM LIMITATION The program will be accurate for conventional two phase flow process flow problems. It is not accurate for critical flow and if the vapor velocity exceeds 300 ft per second then alternative methods based upon equations of state are required. Alchemy Systems is interested in your comments regarding the use of this program and future enhancements that may be desired.