OPTIMAL-DESIGN OF WATER DISTRIBUTION-SYSTEMS USING AN NLP METHOD

In this study, a nonlinear programming approach using the successive q uadratic programming optimization technique is developed for the optim al design of a pipeline network for water supply systems. The proposed method eliminates the equality constraints describing the hydraulics by a suitable choice of dependent and independent variables. The depen dent variables are chosen based on graph theoretic decomposition of th e network structure. This makes it possible to compute analytically th e reduced constraints, objective function gradients, and reduced Hessi an in a very efficient manner. This method of decomposition ensures th at the nodal and loop balances are exactly satisfied and is robust for any initial starting point, able to handle incorrect initial dow dire ctions. The method gives solutions comparable to the previous optimal solutions for the design of new as well as expansion of existing water distribution networks.