芯片冷却过程旋转冲击射流换热特性的数值模拟

采用数值仿真的方法模拟了旋转冲击射流的换热过程，分析了换热过程中喷射孔径、喷射间距、旋转角速度以及流场分布特性对射流冲击换热的表面传热系数与平均换热效果的影响。结果表明，3mm孔径的平均换热效果要强于相同Re数下6mm孔径，而且，大孔径射流时的平均传热系数受角速度的影响要比小孔径时大。角速度的增加使换热板上最大换热系数减小且由驻点向外偏移，加入旋转可以使板上的换热更加均匀，表现为角速度越高，平均表面传热系数曲线越平坦。以上规律为旋转冲击射流在高密度电子芯片散热中的应用提供了理论参考。

Numerical Simulation on Heat Transfer Characteristics of Swirling Jet Impingement for Chip Cooling Process

Based on computational heat transfer and fluid mechanics theory, Heat transfer of round confined air swirling jet impingement with tiny nozzle was investigated by using numerical simulation method to enhance heat dissipation of electronics with high heat flux. The heat transfer processes of swirling jet impingement were simulated. The factors influencing local surface heat transfer coefficient and average surface heat transfer coefficient were analyzed. The investigation revealed that the average heat transfer effect of 3mm nozzle diameter be better than one of 6mm nozzle diameter under the condition of the same Reynolds number. Furthermore, compared with the little diameter nozzle, the average heat transfer coefficient of big diameter nozzle is easy to be changed with angular velocity. The local max heat transfer coefficient decreases when the swirl angular velocity increases, but the swirl jet makes the peak value of local transfer coefficient move away from the stagnation point. For the average heat transfer coefficient of the surface, the jet impingement with swirl velocity is less than that without swirl velocity. With the increase of swirl velocity, the curves become flatness and the heat transfer on the surface becomes uniform.