A Study on the Development of a Water Supply Pipe Network Optimal Operation Program through Minimum Hydraulic Gradient Evaluation

Abstract

Objectives The purpose of this study was to improve the previously developed Eulerian path-based water pipe network operation program. Methods Dynamic programming, integer programming, genetic algorithms, and harmonic search methods were reviewed to overcome memory limitations for program execution. However, it was found that the application of existing optimization techniques has limitations. Therefore, as an alternative method, a minimum hydraulic gradient method based on physical theory was introduced to establish a sequential pipes removal algorithm. Results and Discussion The excellence and the effectiveness of this program were proven through the existing pipe network and optimal path analysis using the EPANET2 input file of the test-bed Y_area. According to the results of the optimal path analysis, in the case of the Y_ area pipe network, 66 pipes and 6,465 m pipe length were analyzed to be possible for removal or maintenance, which was found to be 18.3% of the total pipe length. Conclusion According to the results of the optimal pipe network analysis derived by the minimum hydraulic gradient method, there was little change in the minimum pressure head, and it was evaluated that there was no effect on water supply from a hydraulic perspective. In particular, in terms of water quality, the minimum residual chlorine concentration was found to increase by 0.011 mg/L due to a decrease in residence time and pipe length, which was analyzed to improve water quality.

Keywords

• eulerian path
• water supply pipe network
• optimization
• minimum hydraulic gradient