Author(s): Hanif Chaudhry
Linked Author(s): Mohammad Hanif Chaudhry
Keywords: water hammer; hydroelectric power plants; pumped-storage
Abstract:
WH80 may be used for computing the transient state conditions (commonly known as water hammer) in pumping systems, in hydroelectric power plants, and in pumped-storage schemes; software WHINPUT for preparing or modifying the input data file interactively; an on-line version for cloud computing (allowing lease as short as one month) and TRANSEPANET for input data prepared in EPANET format. For additional details, visit www.compapplications.com. Transient state conditions in a piping system may be produced by opening or closing valves, starting or stopping of pumps, loading or unloading turbines, or varying the discharge or pressure at specified locations with time. The software may also be used to study the governing characteristics of a hydropower plant for small or large load changes (since major non-linearities are included) and to optimize the settings of a turbine governor. The method of characteristics is used to compute transient conditions. Turbo-machines, control devices and other appurtenances are simulated by using the procedures outlined in Applied Hydraulic Transients, third edition, by M. H. Chaudhry, Springer, New York, NY., 2014. The software WH80, originally written in FORTRAN 90, has been converted into Python. Either English or SI units may be used for the system parameters. Input data may be entered manually or interactively by using a separate program WHINPUT, included in the package. To facilitate data input, free format is used. Piping system may be a series or a branching system. Systems having up to 100 conduits, 30 valves, 15 turbines, 15 pumps, 15 surge tanks, 15 one-way surge tanks, five air chambers, five cooling-water condensers and 90 air cavities may be analyzed. (Contact Computer Applications, Inc. for a code for the analysis of larger systems.) Each conduit may be divided into up to 1000 equal-length reaches. For the machine characteristics, data for 16 pumps and 11 turbines over a wide range of specific speeds is stored in the software for use as an approximation when such data is not available. Several options are available for printing the computed results. The computed transient pressures and flows at different cross sections and the flow and other conditions for different appurtenances, such as valves, turbines, pumps, and surge tanks may be saved for post-processing and plotting by other software of User’s choice. The initial steady-state conditions in the system for the specified discharge in different conduits may be computed by using WH, they may be specified as input, or they may be computed by simulating the system for the specified initial boundary conditions for a sufficient time for the conditions in the entire system to converge to the steady state. The software has been verified by comparing the computed results with the field measurements at a number of hydroelectric power plants and pumping systems. The User’s Manual has six chapters: Chapter 1 describes the specification of the system and the preparation of system data. The arrangement of input data, definition of various parameters, and different options for the printing and saving of computed results for post-processing are presented in Chapter 2. This is followed in Chapter 3 by a discussion of the verification of the software. A number of typical examples and how to run the software on your computer or via Cloud are presented in Chapter 4 through 6. A number of empirical relationships and equations, tables, and figures for the values of various parameters are presented in the Appendix.
Year: 2025