如何在增强散热效果的同时降低阻力损失已成为解决中央处理器(CPU)芯片水冷散热问题的关键。本文从翅柱数量、分布、结构以及冷却流体进出口方式等方面对3种水冷散热器进行实验研究,分别在控制冷却流体流量和热流密度的条件下比较不同翅柱结构的压力损失、芯片温度及散热器热阻,得知散热器四角带有导流结构以及水滴形翅柱结构的散热器在热流密度为80W/cm^2、流量为20mL/s时,芯片温度分别为65.5℃和55.5℃,其热阻分别为0.19K/W和0.14K/W,散热性能均优于传统圆柱形翅柱散热器。在流量为60mL/s时,圆柱形翅柱散热器四角设置导流板及水滴形翅柱结构散热器的进出口压力损失分别为34kPa和32kPa,压力损失均小于传统圆柱形翅柱散热器。实验表明在圆柱形翅柱散热器的四角设置导流板,或者改变翅柱形状为水滴形,不仅可强化对流换热,而且可降低流动阻力。
Heat dissipation performance and flow resistance of the traditional circular pin-fins radiator, the cylindrical column fins radiator with fluid guide plates at four comers and hydrofoil pin-fins radiator were studied by changing heat flux and cooling water flow. The pressure drop, chip temperature and thermal resistance of three radiators were measured under the same conditions. The results showed that the chip temperature of the radiator with fluid guide plates at four comers and hydrofoil pin-fins radiator are 65.5℃ and 55.5℃, respectively. The thermal resistance are 0.19K/W and 0.14K/W, respectively at heat flux of 80W/cm^2 and flow rate of 20mL/s. The heat dissipation performance is better than traditional circular pin-fins radiator. At 60mL/s, the pressure drop of the cylindrical column fins radiator with fluid guide plates at four comers and hydrofoil pin-fins are 34kPa and 32kPa, respectively, which is less than traditional circular pin-fins radiator. Compared with the traditional one, the cylindrical column fins radiator with fluid guide plates at four comers and hydrofoil pin-fins radiator have better heat dissipation performance and smaller pressure drop.