Numerical analysis of fluid flow behaviour and thermal performance in radial wavy microchannels

Microchannel cooling systems are investigated for their ability to provide high heat removal with pumping power requirements. Microchannel heat sinks are utilized in applications such as electronic cooling, microprocessors and high heat flux thermal management systems. The hydraulic flow characteristics and thermal performance of radial wavy microchannels with reduced fin heights are examined numerically and compared with those of a radial straight microchannel. Compared to the radial straight microchannel, the radial wavy microchannel demonstrates enhanced fluid mixing, driven by secondary flows resulting from the channels' waviness. These secondary flows disturb boundary layers, keeping the developing flow going in the channel. A numerical study on the effect of reducing fin heights in radial wavy microchannel for enhancing heat transfer performance without significant pressure loss. Conjugate heat transfer simulations are performed for radial wavy microchannel and radial straight microchannel using the commercial CFD solver ANSYS Fluent for various Reynolds numbers (125–275). Nusselt number, pressure drop and performance factor are assessed. The results show that the maximum increase in Nusselt number for radial wavy microchannel with a height ratio of 0.16, compared to radial straight microchannel, is 17%, accompanied by a significant rise in pressure drop at a Reynolds number of 275. The performance factor for various height ratios of wavy microchannels exceeds 1, indicating superior performance.