Numerical Investigation of Vibration‐Assisted Heat Transfer Under Sinusoidal and Square Wave Shapes for Potential Reductions in the Heat Sink and Cooling System Size

ABSTRACT Vibrating heat sinks are highly effective in enhancing cooling by disrupting the thermal boundary layer. However, applying vibration to the base of thin plate fin heat sinks can cause a flapping motion within the fins, further enhancing heat transfer. Therefore, this study investigated the effects of sinusoidal and square wave shape vibrations on the thermal performance of thin fin heat sinks and compared the results with those of conventional heat sink performance. Compared with sinusoidal vibration, applying square wave vibration causes impulsive motion to thin fins, resulting in impulsive flapping motion, which further enhances the cooling effect. The results demonstrate that, compared with conventional heat sinks, vibrations notably enhance the thermal performance of thin fin heat sinks, primarily because of the vibration‐induced flapping motion. A detailed analysis of heat transfer across a range of amplitudes (0–0.003 m), frequencies (0–100 Hz) and Reynolds numbers (1000–2000) reveals that higher amplitudes and frequencies correspond to increased thermal performance. Notably, square wave‐shaped vibrations significantly outperform sinusoidal vibrations, achieving maximum enhancements of approximately 36% in the Nusselt number, compared with 20% with sinusoidal vibrations. Furthermore, employing vibrations allows a possible reduction in the Reynolds number up to 50.3% while maintaining heat transfer comparable to that of static heat sinks, indicating the potential for smaller cooling systems. Additionally, this approach can reduce the required cooling fan power by up to 57% and 35% when square and sinusoidal wave shapes are used, respectively. Finally, this study develops correlations for the Nusselt number that incorporate the vibration frequency, amplitude and Reynolds number, providing practical guidelines for optimizing vibrating thin plate fin heat sink designs.