Document Type : Research Paper
Institute for higher education ACECR, Ahwaz, Khoozestan
Associate Professor, Hydraulic Structures Department, Tarbiat Modares University of Tehran, Iran
The principle of economically optimal design of water conveyance and water supply systems has been one of the major concerns of researchers and designers for along time. In order to design a hydropower plant many combinations of headrace tunnel, penstockand surge tank sizes may be selected.The designalternative that has a maximum benefit-cost ratio is the one which must be sought. be selected that has the maximum benefit-cost ratio. In this paper, unsteady flow analysis is performed initially to get maximum pressures in headrace tunnel and penstocks and maximum water elevation in surge tanks. Based on these results structural design of headrace tunnel, penstocks and surge tanks is done. Total cost of the project is then calculated. Having calculated the head at turbines, sales of power and revenues are determined to get the benefit-cost ratio. It is obvious that for every selected size of involved structures, hydraulic and optimization analyses should be done. The genetic algorithm optimization technique is utilized for optimal design of headrace tunnel, penstocks, and surge tanks. The benefit-cost ratio is considered to be the objective function in the optimization analysis. The hydraulic and optimization analyses have been linked in an iterative procedure to develop a general model for optimal design of hydropower plant projects. The accuracy and convergence of the developed model have been quite satisfactory.