Abstract: The pre-cooler which is the core component，can cause serious frosting when in the process of deep pre-cooling in hypersonic combined propulsion. How to control frosting on the surface of the pre-cooler becomes the key problem to be solved. The research on ultra-low temperature cooling surface coating technology and anti-frosting performance was carried out to control frosting on the surface. The effects of non-condensable gas mixing and high-speed air shear on the frosting process were studied in combination with superhydrophobic coatings. The results show that the frosting time can be delayed to about 7min and the amount of the formed frost was decreased by half at the ZnO superhydrophobic surfaces at the temperature of -20℃. The combination of air shear flow and methanol can decrease frosting on the surface，and the superhydrophobic surface does not freeze within 10 minutes. And at the temperature of -150℃，the frost crystal nucleation rate is significantly lower at the beginning of frosting on the superhydrophobic surfaces.

Key words: Hypersonic combined propulsion；Pre-cooler；Anti-frosting；Non-condensable gas；Super hydrophobicity

摘要： 为了研究高超声速组合发动机预冷器表面的结霜问题，开展了超低温冷却表面涂层技术及其抗结霜性能的研究。研究了不同温度下，不凝性气体混入、高速气流剪切对结霜过程的影响。结果表明:在-20℃，ZnO超疏水表面，可以延迟表面霜晶的形成长达7min，结霜量减少了一半。与单独加风速和单独加入甲醇的外加环境相比，外加流动剪切和甲醇的组合最能够抑制表面结霜，超疏水表面可在10min内不发生水珠的冻结。在-150℃，超疏水表面霜晶的形核率低，仍具有一定抑制结霜的效果。

关键词: 组合发动机；空气预冷器；抗结霜；不凝性气体；超疏水