微方肋冷却系统的换热特性

采用去离子水为冷却介质，对自行设计的不同结构微方肋散热器内的换热特性进行实验研究，结果表明:在进口温度为20 ℃、进口流量为57.225 L/h、底面平均温度为73.4 ℃时，散热器散热量可达2.83106 W/cm2，可以满足当前高热流密度散热需求；当散热面温度一定时，散热量随着散热器进口流量的增加而增加，但增速随散热器底面温度的增加变缓；努谢尔特数随雷诺数的增加而成幂次方增加，常规针肋结构和微针肋结构换热关系式不满足微方肋散热器特性。为了更好地表达微方肋散热器内的换热特性，拟合了微方肋散热器内对流换热关系式。

Heat transfer characteristics of micro fin cooling system

Using deionized water as working fluid, the large height to width rate micro fin cooling systems are proposed. The heat transfer characteristics of these micro fin cooling systems are experimentally studied. It is found that the heat dissipation could reach 2.83×106 W/m2 at the flow of 57.225 L/h and the surface temperature of 73.4 ℃, and the heat sink can meet the demand of high power heat dissipation requirements. When the bottom temperature is fixed, the heat dissipation increases with the rise of flow and finally trends to a constant. The Nusselt number increases with the increase of Reynolds number. The heat transfer performance of the present sink is over predicted by the previous correlations. Therefore, new correlation is proposed to evaluate heat transfer performance of micro fins with consideration of the Nusselt number as a function of the Reyonolds number and Prandtl number.