A numerical study on thermo-hydraulic performance of micro pin-fin heat sink using hybrid pin-fins arrangement for electronic cooling devices

PurposeThis study aims to examine the effect of a combination of hybrid pin-fin patterns on a heat sink's performance using numerical techniques. Also, flow characteristics have been studied, such as secondary flow formation and flow-wall interaction. Design/methodology/approachIn this study, the effect of hybrid arrangements of elliptical and hexagonal pin-fins with different distribution percentages on flow characteristics and performance evaluation criteria in laminar flow was investigated. Ansys-Fluent software solves the governing equations using the finite volume method. Also, the accuracy of obtained results was compared with the experimental results of other similar papers. FindingsThe results of this study highlighted that hybrid arrangements show higher overall performance than single pin-fin patterns. Among the hybrid arrangements, case 3 has the highest values of performance evaluation criteria, that is, 1.84 in Re = 900. The results revealed that, with the instantaneous change in the pattern from elliptic to hexagonal, the secondary flow increases in the cross-sectional area of the channels, and the maximum velocity in the cross-section of the channel increases. The important advantages of case 3 are its highest overall performance and a lower chip surface temperature of up to about 2% than other hybrid patterns. Originality/valuePrior research has shown that in the single pin-fin pattern, the cooling power at the end of the heat sink decreases with increasing fluid temperature. Also, a review of previous studies showed that existing papers had not investigated hybrid pin-fin patterns by considering the effect of changing distribution percentages on overall performance, which is the aim of this paper.

Automated summary

This study investigated the effect of hybrid pin-fin patterns on a heat sink's performance and studied flow characteristics such as secondary flow formation and flow-wall interaction. The findings showed that hybrid arrangements perform better than single pin-fin patterns. Case 3, in particular, exhibited the highest performance evaluation criteria with a value of 1.84 at Re = 900. The study also revealed that the instantaneous change in pattern from elliptical to hexagonal increased secondary flow and maximum velocity in the channel's cross-section.