Analysis of Optimal Solutions of a Benchmark Water Distribution Network for Exploring the Global Optimality of the Current-best Solution.

The optimal design of water distribution networks (WDNs) has always attracted the attention of researchers due to the complexities involved. The general cost optimization problem is categorized as the NLP-Hard problem. Several evolutionary algorithms (EAs) that can explore the entire search from multiple starting points have been developed in the last three decades. The EAs have more chances of reaching the global optimal solution. However, whether these algorithms converge to a global optimal solution or not is always doubtful, as these algorithms do not guarantee the same solution in the two different runs. A two-source benchmark network is considered for which several better solutions have been reported by different researchers in the last 15 years. The available solutions of this network are analysed based on certain parameters, usually observed in the global optimal solution. The main objective of the study is to explore the possibility of achieving a better than the current best-solution, as the global optimality of the current best is not confirmed. Further, the proposed methodology is applied to test the current best solutions of two additional networks. [ABSTRACT FROM AUTHOR]