Thermohydraulic performance of the microchannel heat sinks with three types of double-layered staggered grooves

Abstract

The thermohydraulic performance of the microchannel heat sinks with three types of double-layered staggered grooves are investigated by numerical simulation. The double-layered staggered grooves are staggered rectangular grooves (SRRG), staggered trapezoidal grooves (STLG) and staggered triangular grooves (STRG), respectively. The effect of the shape and geometrical parameters of the double-layer staggered grooves on the fluid flow and heat transfer characteristics are systematically analyzed by multiple physical fields. The comprehensive performances of the microchannels with SRRG, STLG and STRG are evaluated with help of the total thermal resistance (R), R/Rref and thermal enhancement factor (PEC). The results show that the Nusselt numbers (Nu) of the microchannels with SRRG, STLG and STRG are obviously higher than that of the straight microchannel, and the maximum is about 2.3 times of that of the straight channel. For the SRRG, STLG and STRG, the Nu and friction factor of the SRRG are the lowest, while those of the STRG are the highest. the R of the STRG is the lowest while that of the SRRG is highest. The R/Rref of the STRG is the lowest and its minimum value is 0.542. The PEC of the STRG is the highest and its maximum value is 1.61. The comprehensive performance of the STRG is the best, followed by STLG and SRRG. It is demonstrated that the double-layer staggered groove structure can enhance effectively heat dissipation.