Analysis of large scale water distribution systems

A variety of methodologies is currently available for computing flows in water distribution systems. One of these methods is the Newton-Raphson method which regenerates and factorizes Jacobian matrix at each iteration. In this method a great deal of computational effort is consumed in the determination and factorization of the Jacobian matrix.One alternative approach is to use the initial Jacobian matrix throughout, thus avoiding the expense of reforming and triangularizing the Jacobian matrix. However, in this approach the quadratic convergence characteristic of the Standard Newton-Raphson Method is no longer maintained. As a compromise between these two approaches, a class of methods known as Quasi-Newton Methods can be utillized. This paper presents a computer model which incorporates the use of Quasi-Newton Methods in the solution of large scale water distribution systems. Three water distribution systems of varying sizes were analyzed using this method. The computer results obtained using the Quasi-Newton Raphson method were compared to those obtained by the Standard Newton Raphson method. The results show that the Quasi-Newton Method is efficient in handling large scale water distribution systems.