STUDY ON HYDROTHERMAL CHARACTERISTICS OF A CIRCULAR MICROCHANNEL WITH VARYING CIRCULAR AND RECTANGULAR GROOVE

This study numerically examines the characterization of fluid flow and heat transfer in microchannels with grooves of different aspect ratios. Rectangular and circular grooves at different aspect ratios are used as flow turbulence promoters. A correlation is developed for predicting the hydrothermal characteristics of the microchannel using nonlinear regression analysis. Simulations were conducted for a moderate-to-high Reynolds number in the transition-turbulent flow regime. The influences of parameters like inlet velocity, groove depth, and groove shape on the hydrothermal properties of the microchannel are examined. Analysis of the result shows that, with an increase in the groove's aspect ratio, the Poiseuille and Nusselt numbers decrease. The pressure drops across the microchannel increase with an increase in Reynolds number, and it decreases with an increase in groove depth. The microchannel with a circular groove exhibits a higher friction factor and pressure drop and, in turn, higher heat transfer than the rectangular microchannel.