Developing of constructal theory concept for plate-fin heat exchanger modelling, design and optimisation

Abstract

In this paper, the modelling, design and optimisation of plate-fin heat exchangers has been carried out by applying the concept of constructal theory. Current heat exchangers design method call for use of one scale flow structure but constructal plate-fin heat exchanger is designed by multiple length scales with more than one construct. The objective function is to investigate the geometries that give best heat recovery or higher cold stream outlet terminal temperature. The design parameters include number of constructs and geometric variables of each construct. The constructal heat exchanger volume and heat transfer area are kept constant and equal to the volume and heat transfer area of the optimised ordinary heat exchanger. The potential applicability and effectiveness of the current methodology is demonstrated on a case study. The optimisation of the case study reveals higher heat recovery in constructal plate-fin heat exchanger in comparison with ordinary plate-fin heat exchanger.