Configuration optimization of a membrane-based total heat exchanger with cross-corrugated triangular ducts considering thermal economy and entropy generation

Abstract

Membrane-based total heat exchanger with cross-corrugated triangular ducts is a new structure, and the changing-section channels in the heat exchanger would make fluid undergo periodic contraction and expansion, which provides an effective approach for strengthening convective heat and mass transfer. Numerous studies proved that the geometric structure have great influence on performance of this type of heat exchanger core, whereas studies about structure optimization considering both thermal irreversibility and economic benefits are rare. In the present study, the total economic return and total entropy generation rate are analyzed as two objective functions simultaneously to evaluate thermal economic and thermal irreversibility performance respectively. A global sensitivity analysis was conducted to select the more sensitive paraments from the six key geometric design parameters: the channel height H, apex angle θ, channel number of each layer on fresh air side nf, channel number of each layer on exhaust air side ne, and the total number of plates nh. They are optimized by the multi-objective particle swarm optimization (MOPSO) algorithm by taking into account entropy generation minimization (EGM) and economic return maximization. The convergence and stability analysis of the algorithm is proposed and the result informs a good application. The optimal geometric design scheme is obtained from the Pareto set according to the normalization method. A parameters analysis was also conducted to study the influence of geometric parameters on the thermal irreversibility and thermal economy performance of the heat exchanger.

Keywords

• Total heat exchanger
• Membrane
• Cross-corrugated triangular ducts
• Entropy generation rate
• Economic return
• Global sensitivity analysis