带翅片的小型平板CPL蒸发器相变传热的数值模拟

提出一种小型平板毛细抽吸两相流体回路（CPL）系统来实现电子元器件散热，分析了其工作原理及特点。针对小型平板式CPL蒸发器的结构特点，分析了蒸发器侧壁导热所引起的侧壁效应对CPL传热能力的影响，提出小型平板CPL存在侧壁效应传热极限。为了提高系统的传热能力，蒸发器下壁增设了散热翅片。建立了小型平板CPL蒸发器毛细多孔芯的二维气液两相分层饱和多孔介质模型，金属壁面及工质气、液空间区域耦合的数学模型，并用SIMPLE算法对模型进行求解。数值研究表明，蒸发器受热面的温度水平较低，均温性较好。蒸发器采用翅片可以增加多孔芯内的温度梯度，使芯内温度分布更加合理;可以降低加热表面以及下壁温度，提高了侧壁效应传热极限，增强了系统的传热能力。

Numerical simulation of heat transfer with phase change in small-scale flat capillary pumped loop finned evaporator

The small-scale flat capillary pumped loop(CPL)for the cooling of electronic apparatus was presented,and its operation principle and characteristics were analyzed.Based on the structure characteristics of small-scale flat CPL evaporator,the effect of metal side wall conduction of evaporator on the CPL work limit was analyzed,and the heat transfer limit of side wall effect was introduced.In order to improve the heat transfer capacity of CPL,fins were added on the bottom of evaporator.The flow and heat transfer in the porous structure were modeled by using two-phase layered saturated porous model,and the conduction models of metal wall and fluid region were established.The entire evaporator was solved with the SIMPLE algorithm as a conjugate problem.The numerical results showed that the heated surface temperatures of the evaporator were low,and the temperature difference along the heated surface was small.The temperature gradients in the wick structure of evaporator with fins increased,and the temperature distribution in the wick structure was reasonable.The temperatures of heated surface and bottom metal wall of finned evaporator decreased,and the heat transfer capacity was improved remarkably.