To solve the heat dissipation problem of electronic devices, the flow and heat transfer features of elastic pillar with different initial inclinations in microchannel are numerically investigated. Furthermore, the influences of dynamic characteristics and inclination angle of the elastic pillar on fluid heat transfer performance, hydrodynamic friction factor, and overall hydrothermal efficiency are probed. The results indicate that 1.25 μm oscillation is generated when the inclination angle of the elastic pillar is 0.2π. This small amplitude is not conducive to the generation of vortices. On the other hand, an elastic pillar in a fully flapping mode can generate periodic vortices, which is more conducive to the disturbance to the boundary layer and the mixing of cold and hot fluids, thereby enhancing heat transfer. In the range of Re from 800 to 1 200, the elastic pillar has the optimal inclination angle of 0.6π. Under the optimum working condition, at the expense of high mechanical loss, the heat transfer performance of the fluid can be improved by 63.5%, and the total hydrothermal efficiency can be increased by 7.5%.
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