Numerical investigation of heat transfer performance in parallel and symmetric wavy microchannel heat sinks

Microchannel heat sinks have advantages such as a high surface area-to-volume ratio, a large heat transfer coefficient, and lightweight design, making them crucial for microelectronics and aerospace applications. Numerical simulation was conducted to analyze the fluid flow and heat transfer characteristics in the newly designed heat sink at Reynolds number ranging from 147 to 736.The symmetric wavy microchannel heat sinks were compared with the parallel wavy microchannel heat sinks based on friction coefficient, Nusselt number, and comprehensive performance factor. The results indicate that periodic variation in the cross-sectional area of the symmetric wavy microchannels generates vortices at the valleys, enhancing fluid mixing. In contrast, the fluid in the parallel wavy microchannels exhibits a wave-type flow pattern, where the wavy structure disrupts the flow boundary layer. The fluid flows along the streamlined boundary with less flow friction. This enables heat transfer enhancement under lower pressure drop conditions. The geometrical parameters for optimal heat transfer performance are obtained by adjusting the amplitude ratio(?). The comprehensive performance factor for the parallel wavy microchannels, with a Reynolds number of 736 and a value of ? = 4, is 1.64.