Linear Programming based Model for Design of Looped Water Distribution Networks with Redundancy

Abstract

A new linear programming based two-phased methodology is suggested for design of looped water distribution networks with redundancy. The redundancy is provided against failure of pipes and a network is designed to sustain failure of any one of the link without affecting nodal supplies in a part or full. In the first phase, network is designed under normal pipe working conditions for assumed flow distribution using linear programming. The performance of designed system is checked using node-flow analysis for one pipe-failure conditions and most critical pipe failure condition is obtained in the second phase. The linear programming formulation in the first stage is appended to incorporate constraints for critical pipe failure conditions and solved. This process of successive addition of constraints in first phase continues until network design becomes satisfactory to sustain failure of any single pipe. The methodology is general and successive addition of constraints reduces the size of problem to be handled at a time. The methodology can be used for any type of flow-distribution. However, flow-distribution based on Chiong’s model is observed to provide better design. The methodology is illustrated with example networks taken from literature.