Economic design of water distribution systems in buildings

J. Júdice, A. Silva-Afonso, C. Baptista and L. M. Fernandes

Abstract

In this paper an engineering optimization problem is introduced which arises in hydraulics and is related with the application of a new criterion for the sizing of water distribution piping in large buildings. The optimization model seeks the most adequate interior piping diameters to be applied in the various pipes in the circuit, that must belong to a finite collection of standard values and minimize the overall installation cost according to some boundary conditions. A concave nonlinear program formulation of the problem is studied and a branch-and-bound algorithm is presented for its solution. A procedure is proposed to obtain a feasible solution with standard values from the optimal solution of the concave problem. An analysis of the performance of the algorithm for a given real-life problem and an economical interpretation of the solution found are also included and show the appropriateness of the model and of the optimization techniques for their purposes.