三种不同毛细芯的有效导热系数的实验研究

Experimental Study on Effective Thermal Conductivities of Three Kinds of Capillary Wicks

采用水和乙醇为工质,施加不同的热载荷,获得了氮化硅、氧化锆及3D打印钛合金等三种毛细芯在干态、含水和含乙醇状态下的有效导热系数。研究显示:三种干态毛细芯的有效导热系数都随毛细芯平均温度的升高而增大;氧化锆、3D打印钛合金毛细芯在含水和含乙醇状态下的有效导热系数随毛细芯平均温度的变化呈现出先增大后减小的趋势,最后趋向于自身的热导率;在含水状态下,氮化硅毛细芯的有效导热系数随毛细芯平均温度的升高呈现出先增大后减小的趋势,在含乙醇状态下,氮化硅毛细芯的有效导热系数随毛细芯平均温度的升高没有明显变化。

Using water and ethanol as the working fluids,the effective thermal conductivity of three kinds of capillary wicks in dry,water-containing and ethanol-containing states were obtained under different heat loads. It was found that the effective thermal conductivity of the three dry capillary wicks increased with the average temperature of the capillary wick. The effective thermal conductivity of zirconia and 3D-printed titanium alloy wicks in both water-containing and ethanol-containing states increased first and then decreased with the increase of the average temperature of the capillary wick,and finally tended to its own thermal conductivity. Under the water-containing state,the effective thermal conductivity of the silicon nitride capillary wick increased first and then decreased with the increase of the average temperature of the capillary wick. Under the ethanol- containing state,the effective thermal conductivity of the silicon nitride capillary wick did not change significantly with the increase of the average temperature of the capillary wick.