Fuzzy Multiobjective Optimization of Water Distribution Networks

An original approach to the optimal design of water distribution networks is presented in this paper. Multiobjective optimization is applied, i.e., minimizing costs and maximizing a benefit/quality function, the tradeoff curve being produced by a genetic algorithm. Fuzzy reasoning is introduced to the evaluation of benefits for each potential solution. A number of criteria are introduced, individually assessed by fuzzy membership functions and combined as a whole using fuzzy aggregation operators. Additionally the paper includes a novel approach for the simulation of tanks as network storage components within the genetic algorithm, taking into account the tank shape. The model is applied to a well-known example from the literature, the "Anytown" water distribution network, to benchmark the results. Comparison of results shows that the model manages to find a better solution than any other previous approach in terms of cost, despite the multiple criteria applied for the benefit function being more extensive and stricter.