Friction and Colburn factor correlations and shape optimization of chevron-type plate heat exchangers

The unsteady numerical analysis with a large-eddy simulation (LES) has been described to examine the characteristics of pressure drop and heat transfer for chevron-type plate heat exchangers. For validation of the numerical results, experiments were carried out; good agreement was found, with a maximum error of 10%. Correlations of friction factor and Colburn factor were determined by taking various geometric parameters (chevron angle beta, pitch p, and height h) and working fluids into account. Design optimization was also conducted by using the micro-genetic algorithm and considering the JF factor as an objective function. The optimal points (beta = 66.5 degrees and p/h = 2.73) were almost constant, regardless of the Reynolds number. (C) 2015 Elsevier Ltd. All rights reserved.