Parametric Study of Pin-Fins Microchannel Heat Exchanger

Abstract

MEMS heat exchangers use microchannels to increase the surface area of contact between the moving fluids. MEMS heat exchangers are typically utilized for processor chip cooling applications. This study investigates the influence of geometric and operating parameters on performance of a pin-fins microchannel heat exchangers. ANSYS Workbench is used for modelling. The mathematical model consists of the continuity equation, Navier-Stokes equation, and energy equation. Water is taken to the fluid in this study. The boundary conditions of the model consist of the inlet temperature of the fluids, inlet flow rate of the fluids, fluid velocity on the walls (set v = 0), outlet pressures (set to Pout = zero), and temperature gradient at the outlet (set equal to zero). The influence of hydraulic diameter, pin fins diameters, structural material, and Reynolds number on the effectiveness of heat exchanger is studied. Studies are carried out for Reynolds number varying between 100 and 2000. The materials considered for this study are stainless steel, silicon, and copper. The effectiveness is determined using the inlet and outlet temperatures of the fluids. The thermal performance of MEMS heat exchanger is influenced by the hydraulic diameter and pin-fin diameter. The thermal performance of the MEMS heat exchanger increases with reduction in Reynolds number.