梯形微槽道表面池沸腾换热性能研究

池沸腾换热表面的结构对其沸腾换热性能具有重要影响。为了进一步强化在较低表面过热度时池沸腾换热的性能，提出了新型梯形微槽道池沸腾换热表面，采用可视化实验方法研究了饱和温度下去离子水在该表面的池沸腾换热性能。结果表明：与光滑平面相比，梯形微槽道表面可以降低起始沸腾表面过热度；在相同表面过热度时，随着下底长度的增大、下底角角度的减小，梯形微槽道表面的热通量增加，换热能力增强。下底长度为1.2 mm、下底角度为45°的梯形微槽道表面具有最低的起始沸腾表面过热度（1.4 K）；在表面过热度为8.3 K时，其热通量能达到1.2×10⁶ W·m^-2，为相同表面过热度时光滑表面的24.0倍。较大的下底长度和较小的下底角角度有利于增强梯形微槽道表面的池沸腾换热性能。

Study on pool boiling heat transfer performance of trapezoidal microchannel surface

The structure of pool boiling heat transfer surface has an important influence on its boiling heat transfer performance. In order to further enhance the pool boiling heat transfer performance at lower surface superheat, a new type of pool boiling heat transfer trapezoidal microchannel surface was proposed, and the pool boiling heat transfer performance of deionized water on the surface at saturated temperature was studied by the visualization experiment method. The results show that the trapezoidal microchannel surface can reduce the superheat of initial boiling surface compared with smooth surface. At the same surface superheat, with the increase of the bottom length and the decrease of the bottom angle, the heat flux and heat transfer capacity of the trapezoidal microchannel surface increase. The trapezoidal microgroove with a bottom length of 1.2 mm and a bottom angle of 45° has the lowest initial boiling surface superheat (1.4 K). When the surface superheat is 8.3 K, the heat flux can reach 1.2×10⁶ W·m^-2, which is 24.0 times as much as that of the smooth surface at the same surface superheat. The larger bottom length and the smaller bottom angle are beneficial to enhance the pool boiling heat transfer performance of the trapezoidal microchannel surface.