Improved complementary reservoir solution to evaluate nodal outflow under pressure-deficient conditions

Abstract

Water distribution system supplies water to the consumers as per the designed condition if requirement of water matches with designed level. It seldom matches the designed condition during operation scenario. Uncertainty of the demand, failure of components, diversion of water, aging of pipeline, permanent increase in the demand at certain supply node, fire demand etc. creates deficit in supply. In such situations, it is important to assess actual flow that can be delivered from nodes so that the authority concerned can take up alternate steps to tackle the situation immediately. Though there are several methods available to analyze pipe networks under pressure-deficient conditions, researchers evolve new approaches or improve existing approaches that can be implemented easily with existing software. This paper proposes an improved method for pressure-driven analysis to minimize the number of addition or deletion of complementing reservoirs in complementary reservoir solution approach. Main logic of the improved method is that no supply from a node is possible if the pressure drop at a node exceeds the difference in hydraulic gradient of source and maximum pressure drop node. The proposed method is applied to three benchmark networks and results of the study show that the improved method simplifies the analysis process by reducing number of addition of complementing reservoirs.