MODELING RESERVOIR EVAPORATION LOSSES BY GENERALIZED NETWORKS

Using a generalized network formulation, the nonlinear evaporation los s function of a reservoir is directly incorporated in a water-supply-o ptimization model. The nonlinear function is first piecewise-linearize d and the resulting line segments are represented by a series of arcs. An appropriate arc-flow multiplier is used to reflect the slope in ea ch line segment. A convex penalty function is then used to preserve th e order of arc-flow fulfillment. The proposed formulation can be appli ed to model other forms of losses in a water-supply system and it elim inates iterative solutions as required by a pure network formulation. The overall management model is solved by an embedded generalized netw ork algorithm (EMNET), which is designed to solve a linear-programming problem with an embedded generalized network substructure. Together w ith our previous study EMNET is proven to be an efficient tool in solv ing general water-supply-optimization problems.