Experimental Investigation and Performance Optimization of a Cross Flow Heat Exchanger by Entropy Generation Minimization Approach

摘要

The exergy loss and performance optimization of a cross flow heat exchanger (CFHE) with air and hotwater as working fluid have been experimentally investigated. Experiments are performed on various mass flowrates of hot water and air over a ranges of 0.015 kg.s 1 0.04 kg.s 1 and 0.117 kg.s 1 0.763 kg.s 1 respectively. Tovalidate the results of the present study, they are compared with available data in literature through which areasonably a good agreement is obtained between them. This study demonstrates the successful application ofTaguchi approach for optimal design of the (CF HE). The effects of design parameters and two differentoperating conditions such as the fin pitch, the inside tube diameter and the mass flow rate of water and air onexergy loss are investigated. In the Taguchi experimental design method, exergy loss is considered asperformance parameter and it is revealed that parameter combinations such as h=0.0163 kg.s 1 , a=0.1175 kg.s1 , d i =0.0199 m and F p =0.00259 m resulted optimum performance. Contribution ratios of each parameter onexergy loss are assessed. Mass flow rate of air is determined to be the most effective parameter on exergy losswith a contribution ratio of 51.26 % followed by mass flow rate of hot water, fin pitch, and diameter contributionratios of 35.91 %, 7.02 % , 5.79 % respectively.