小型平板CPL蒸发器预热驱动过程研究

INVESTIGATION ON STARTUP PROCESS CHARACTERISTICS OF SMALL-SCALE FLAT CAPILLARY PUMPED LOOP EVAPORATOR

分析了小型平板CPL蒸发器毛细多孔芯上下表面温差对启动的影响,建立了蒸发器满液启动的数学模型。结果表明,对不同的金属外壁,多孔芯上下表面平均温差存在一个最大值,铜壁时,温差较小,侧壁效应明显;采用不锈钢壁及上壁铜、侧壁下壁不锈钢时,温差大,侧壁效应小;采用不锈钢外壁时蒸发器加热面的温度过高。上壁采用导热系数大、侧壁下壁为导热系数小的金属对小型平板CPL蒸发器的正常启动以及降低加热表面温度非常有利。

The influence of temperature difference between upper surface and bottom surface of wick structure on startup process of the small-scale flat capillary pumped loop evaporator is analyzed, and the unsteady heat transfer model of evaporator in the fully-flooded startup stage is presented. The numerical results show the average temperature difference between upper surface and bottom surface of wick has a steady maximum value corresponding to different material metallic wall. For the copper wall, the average temperature difference is small, and the effect of heat conduction of side wall on the startup process of evaporator is great. For the stainless steel wall, the average temperature difference is large, but the temperature of the heated surface of evaporator is high. For the combined wall which includes upper copper wall and side and bottom stainless steel wall, the average temperature difference is large and the heated surface maintains a suitable temperature level. The combined wall is advantageous for successful startup of small-scale flat CPL evaporator and decreasing the heated surface temperature of evaporator.