Numerical investigation of microchannel heat sink with novel ogive shape ribs

Abstract

In this study, 3D numerical conjugate heat transfer modeling is used to investigate the thermal and hydraulic characteristics of the microchannel heat sink (MCHS) with different configurations of novel ogive shape ribs on channel walls. It was found that new proposed MCHS configurations with ogive ribs have a high Nusselt number as compared to the smooth MCHS because ogive ribs enhance the heat dissipation between channel walls and fluid by continuously interrupting the thermal boundary layer development. MCHS configuration with ogive ribs mounted on bottom wall improves the Nusselt number of smooth MCHS by 1.13–1.87 times, while MCHS with ogive ribs mounted on both side walls and MCHS with ogive ribs mounted on bottom channel wall improve Nusselt number by 1.12–1.70 and 1.08–1.59 times, respectively, at Re 100–1000. In terms of thermal enhancement factor criterion, the MCHS with ogive ribs on side walls shows superior performance at Re 100–300 and has the highest thermal enhancement factor. While MCHS with ogive ribs on bottom wall outperformed other configurations in terms of thermal enhancement factor at Reynold number > 300. A maximum thermal enhancement factor of 1.42 is reported for MCHS with bottom wall ribs ogive at Re = 1000.