小型轴流散热风扇出口换热特性研究

Study on outlet heat transfer characteristics of small axial cooling fan

以某品牌服务器内小型轴流散热风扇为研究对象,利用可压缩气体控制方程组定性分析了风扇内部不同时刻的温度场变化趋势,并引入风扇对流换热系数,定量分析了风扇内部流场的对流换热能力。结果表明,涡流的剧烈运动提升了风扇的对流换热能力;受风扇强制对流驱动的输入热源,优先沿端壁传递热量到远场;在风扇出口轮毂附近存在大量的低温区,该低温区的平均温度比入口热源温度要低3℃左右。

The small axial flow fans used in a certain server for heat dissipating are selected as the research object, and the compressible gas control equations are used to analyze qualitatively the trends of temperature field inside fans at different time. The convection heat transfer coefficient of the fans is introduced to analyze quantitatively the convective heat transfer capacity of fan internal flow field. The results show that vigorous exercise vortex enhance the convective heat transfer capacity of the fan. The input heat source driven by forced convection from fans spreads heat to the far field priority along the end wall. There are a lot of low-temperature region near the outlet of the fan hub, and the average temperature of the above low temperature region is lower about 3 ℃ than that of the inlet temperature.