Simultaneous synthesis of heat exchanger network with stream splits

A novel simultaneous synthesis approach is proposed for annual general cost-optimal heat exchanger network with stream splits.The presented method formulates a simultaneous synthesis mathematical model without the assumption of isothermal mixing,which is a complex mixed integer nonlinear mathematical programming model based on stage-wise superstructure model.In order to control the solution complexity of cybernetic model efficiently,the parallel structure with stream splits and series structures with no stream splits are considered simultaneously in the stage-wise superstructure.An efficient two-level optimization algorithm is used for solving the presented model.At the upper level,the network structures are optimized using genetic algorithm.At the lower level,heat load of units and stream-split heat flows are optimized through particle swarm optimization algorithm.Two benchmark problems and one large-scale synthesis problem of heat exchanger network are presented to show the applicability of the proposed methodology.