Pinch analysis of heat exchange problems with uncertain parameters

A system method is proposed to analyze pinch change of heat exchange problems with uncertain stream flowrates and temperatures. By an analysis of the maximum heating point and maximum cooling poi nt of uncertain parameters, existence of pinch jump can be determined. Based on the principle of reduced temperature interval analysis, a sufficient and necessary condition is derived for each stream supply temperature to determine if it is possible to become pinch within the specified range of uncertain parameters, then this range may be partitioned into different pinch regions. The study is a foundation for the flexibility analysis, synthesis, and retrofit of heat exchanger networks.