The numerical simulation with staggered alternation locations and multi-flow directions on the thermal performance of double-layer microchannel heat sinks

Highlights: • Staggered alternation structure in double-layer microchannel heat sinks is studied. • Flow characteristics and tracelines of SFAS in microchannels are described. • Temperature redistribution on substrate for different layouts are compared. • Thermal performance and pressure drop characteristics are fully investigated. • Changing the locations of SFAS significantly improves the thermal performance. • The SFAS located near the center of channel has the gradients of higher temperature. -- Abstract: The novel staggered flow alternation structure (SFAS) proposed in prior study has proved to be an efficient way in improving the overall thermal performance with acceptable pressure drop penalty in Double-layer Microchannel Heat Sinks (DMHSs). Based on the prior design, a further numerical investigation concerning the optimum location of SFAS in DMHSs is presented. The corresponding temperature fields, Nusselt number, flow fields, pressure drop and thermal characteristics are presented through verified computational mode. In addition, the effect of flow arrangements such as concurrent, upper-inlet/lower-inlet countercurrent arrangement on the thermal performance are studied in more details. The best thermal location of SFAS in the DMHSs is found to be based on the alterable locations and multi-flow directions. Yet, changing the location of staggered alternation structure does not lead to an appreciable rise of pressure drop penalty in DMHSs. However, the improvement in thermal performance for upper-inlet countercurrent arrangement is significant. Placing the SFAS in the middle of the DMHSs ensures the best overall thermal performance.