脉动流强化翅片散热器数值模拟研究

Numerical study on finned radiator under pulsating flow for heat dissipation enhancement

采用数值模拟的方法,研究脉动流作用下翅片散热器的散热效果,分析脉动振幅和脉动频率对散热性能的影响。结果表明:脉动流能增强翅片散热器的散热效果;随着脉动振幅增大,瞬时换热性能和瞬时阻力性能波动越来越强,平均换热性能和平均阻力性能增加;存在最佳振幅使综合换热性能最高;随着脉动频率增大,瞬时换热性能变化不大,平均换热性能逐渐减小;瞬时阻力性能波动剧烈且波动幅值增大,平均阻力性能减小;存在最佳频率使综合换热性能最高。

A numerical method is used to study the heat dissipation performance of a plate-fin radiator under pulsating flow.The effects of pulsating amplitude and frequency on the heat dissipation performance are analyzed.The results show that the pulsating flow can somewhat enhance the heat dissipation performance of the radiator.The transient heat dissipation performance and the transient flow resistance increase as the amplitude increases.An optimal amplitude exists where the radiator has the highest overall heat dissipation performance.With the increase of the frequency,the radiator transient heat dissipation performance is nearly invariable;while the average heat transfer performance decreas es gradually.Meanwhile the transient resistance fluctuates sharply,the fluctuation amplitude increases while the average flow resistance decreases.There is also an optimal frequency that leads to the highest overall heat dissipation perfor mance of the heatsink.