Optimal design of a converging diverging channel for convective heat transfer enhancement in fully developed turbulent air flow

Abstract

The optimization operation has been performed with ANSYS Response Surface Optimization Tool to find optimum channel geometry for converging-diverging channels. Steady state, three dimensional, turbulence, viscous, compressible, single-phase Newtonian flow is assumed through the channel with rectangular cross section. In the study, output parameters have been selected as Colburn factor and Darcy friction factor. Effects of channel width, wavelength and amplitude of converging-diverging channel on output parameters have been examined and nondimensionless results have been obtained for optimal geometries for three different Reynolds numbers (Re = 4400, 5600 and 6700). To analyze the thermal-hydraulic performance of the optimum wavy channel, thermal performance factors (TPF) are calculated. Results showed that optimized channel is more efficient than straight channel, TPF values for optimized channel were ranged from 1.7 to 1.4 over the range of Re studied.