Topological Optimisation Design of Nanofluid-Cooled Microchannel Heat Sink Using a Three-Layer Thermofluid Model for Electronics Cooling

Bin Zhang^1,*, Xuanyan Lu¹, Zhigang Qin², Yibo Mo³, Chenwei Wang¹, Sihui Hao¹, Yixiang Song¹, Jianyun Xu¹, Zhifeng Zhang⁴, Xu Long^1,*
1 Department of Engineering Mechanics, School of Mechanics and Transportation Engineering, Northwestern Polytechnical University, Xi’an, China
2 East Energy Storage Technology Co., Ltd., Xi’an, China
3 Beijing Frontier Power Technology Co., Ltd., Beijing, China
4 Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, USA
* Corresponding Author: Bin Zhang. Email: email ; Xu Long. Email: email

Computer Modeling in Engineering & Sciences https://doi.org/10.32604/cmes.2026.086481

Received 31 May 2026; Accepted 27 August 2026; Published online 14 September 2026

Abstract

Nanofluid-cooled microchannel heat sinks (NCMHS) feature high heat dissipation efficiency and serve as a critical thermal management solution for electronic devices. This study employs a computationally efficient multi-layer modeling approach to conduct three-layer topological optimisation of the NCMHS. The flow and heat transfer within the NCMHS are described using a single-phase nanofluid-based thermofluid model that accounts for temperature-sensitive fluid properties. On this basis, a three-layer thermofluid model of the NCMHS is constructed by introducing assumptions regarding the velocity profile and an adaptive temperature profile in the thickness direction, together with the interlayer coupled heat flux derived from Fourier’s law. This model describes the conjugate heat transfer in the fluid channel and the heat conduction in the top and bottom plates in a two-dimensional manner, while comprehensively accounting for the influences of out-of-plane flow boundaries and heat transfer. Comparative validation against a full three-dimensional model demonstrates that the developed three-layer model achieves good numerical consistency. Based on this model, a three-layer topological optimisation framework for the NCMHS is further established by representing the channel layout with a fictitious density field. Numerical examples investigate the influences of temperature-sensitive fluid properties, pressure drop, heat source characteristics, and nanofluid properties on the optimized design of the NCMHS. The results elucidate that temperature-sensitive fluid properties significantly influence the optimized design. As the pressure drop increases, the optimized design tends to become more complex. In addition, reducing the nanoparticle volume fraction promotes the emergence of more branched channels in the optimized design.