Hydrodynamic influence on thermal management of flexible heatsink devices embedded with out-of-plane intricate microchannel design

This study examines the thermal management efficacy of a 3-D printed microfluidic heat sink device with an intricate microchannel design. The performance of the presented device was experimentally compared to device with contemporary rectangular microchannel for different base material compositions and flow parameters to further understand the complex heat transfer trade-off between heat conduction and convection. The study found that upon tuned with a relatively low flow rate of 10 μLmin⁻¹, the heatsink device made from nanocomposite material, featuring an intricate 3D design, generates the lowest hotspot temperature due to uniform heat dissipation. However, when flow rate was increased to 120 μLmin⁻¹, the phenomenon reverses and PDMS-based devices with intricate channel perform better compared to PDMS nanocomposite-based devices. There was concurrent occurrence of the aforementioned phenomena at various temperature settings of 338 K, 358 K, 373 K, and 388 K. Numerical simulation reveals that relatively high flow rates create vortices, which significantly alter the heat transfer characteristics of the devices. Along with its primary application of on-demand flexible electronic cooling, with optimal flow tuning, the applications of the proposed device can be further extended to the thermal management of batteries, industrial 3D-printer nozzle heads, and artificial organ cooling, etc.