Parameter study of laminar flow and heat transfer in an interrupted microchannel heat sink with ribs

The enhanced heat transfer mechanism and parameter optimization of an interrupted microchannel heat sink with rectangular ribs (IMCHS-R) was numerically studied for Reynolds number ranging from 100 to 900, using ANSYS Fluent. Interrupted microchannel heat sinks with different kinds of rectangular ribs having different width, length, and locations were compared with a straight microchannel and microchannel interrupted chambers. The results indicated that the heat transfer and flow resistance were mainly strengthened at the sudden converging area and narrow channels, and the secondary flow area did not show a positive effect on heat transfer. The IMCHS-R with W₂/W₁ = 0.3 and L₂/L₁ = 0.7 presented the best behavior from both PEC and S_tot-ave at Re = 500–700. The heat transfer performance can be improved 2.0 times compared to the straight microchannel heat sink and the PEC can reach a value larger than 1.5. However, the rib location has a little effect on the enhanced heat transfer performances.