设计并通过3D打印制备了3种毛细芯结构：无嵌入式槽道（蒸汽槽道）毛细芯、嵌入式槽道毛细芯（同孔径槽和异孔径组合槽）。通过实验研究了毛细芯蒸汽槽道对环路热管（Loop Heat Pipe,LHP）传热性能的影响。实验结果表明：在低热负荷启动时，3种毛细芯均能成功启动且蒸发器出口（te-out）及冷凝器进口（tc-in）由于气液两相流的存在出现周期性温度振荡；嵌入式槽道毛细芯启动响应快（76 s）、温度振荡（tc-in）幅度小（±1.0 ℃），同孔径槽毛细芯稳定温度低（36.8 ℃），异孔径组合槽毛细芯由于大孔径（500 μm）不利于低热负荷下的蒸发，启动稳定温度高（38.7 ℃）；在变热负荷运行过程中，嵌入式槽道毛细芯有效蒸汽排出面积更大、蒸汽干度更高，在中、高热负荷，温度振荡（tc-in）得到明显改善；异孔径组合槽设计更有利于内部产生蒸汽高效排出，在高热负荷工况下，异孔径组合槽毛细芯壁面温度为85.0 ℃，比无嵌入式槽道毛细芯低了8.0 ℃。

Three types of wick structures were designed and prepared by 3D printing in this paper, including the wick without embedded groove(steam groove)and the wick with embedded groove(sameaperture groove and heteroaperture combination groove).The effect of the wick steam groove structure on the heat transfer performance of the loop heat pipe(LHP) was studied by experiments.The experimental results show that all three kinds of wicks can be started successfully at startup of low thermal load, and periodic temperature oscillations appear at the evaporator outlet (te-out) and the condenser inlet (tc-in) due to the presence of gasliquid twophase flow.The wick with embedded groove structure has a fast startup response (76 s) and a small temperature oscillation (tc-in) range (±1.0 ℃).The wick with sameaperture groove has a low stable temperature (36.8 ℃).And the wick with heteroaperture combination groove has a highly stable temperature (38.7 ℃) due to the large aperture (500 μm) which was not conducive to evaporation at low thermal load.During the operation at the variable thermal loads, the wick with embedded groove has a larger effective steam discharge area and a higher steam dryness, and the temperature oscillation (tc-in) is improved obviously at the medium and high thermal loads.The vapor can be easily vented from the wick with the heteroaperture combination groove.At high thermal load, the wall temperature of the wick with heteroaperture combination groove is 85.0 ℃, which is 8.0 ℃ lower than that of the wick without embedded groove.

TK172.4

国家自然科学基金重点项目(51736007)