Layer assignment and arrangement optimization for multi-stream plate-fin heat exchanger design.

The design of layer assignment and arrangement still remains an obstacle for optimizing the performance of the multi-stream plate-fin heat exchangers. A novel layer assignment and arrangement modelling and optimization method are proposed in this paper. It is a combination method of the equipartition of entropy production and the balance of local heat load, by means of which the pressure drop rise and heat transfer performance drop caused by inappropriate layer assignment and arrangement could be reduced to a large extent. The specific entropy generation rates of heat transfer and fluid friction are adopted as the dual objective functions and simultaneously minimized. This model exhibits a good robustness and high efficiency when used to design main heat exchanger in air separation plants, and simultaneity optimizes the plate fin configurations and layer arrangement.