Abstract: The experimental study on the impact between droplet and real coating surface samples based on high-speed camera is conducted， in order to analyze the development of spray droplets after hitting the coating wall of combustion chamber， and the effects on combustion and heat transfer of the bipropellant centrifugal engines. The velocity， angle and particle size of the droplet impinging on the coating walls in the variable situation， including sticking， spread， breakup， splash， suspension and rebound， at different wall temperatures and diverse impact Weber numbers can be observed in this experiment. It is proved that the difference of coating surface state has significant influence on the droplet’s impinging behavior. Through this experiment， the mechanism and mathematical models of two kinds of coatings based on the wall temperature and impact Weber number are established. Coupled with the chemical reaction model， the analysis of combustion and heat transfer can be carried out to verify the higher accuracy of the new model， compared to the simulation result by using OA model and measured data in the engine firing test.

Key words: Bipropellant engine;Coating wall;Atomizing droplets;Impact experiment;Mechanism division;Modeling

摘要： 为了研究双组元离心式发动机的喷雾液滴在撞击燃烧室涂层壁面后的发展行为，及其对发动机燃烧和传热的影响，进行了液滴与真实的涂层试样的机理性试验。通过试验，使用高速摄影装置观察了液滴在不同温度和入射韦伯数We的条件下撞击涂层试样后的情况，包括撞击后粘附、铺展、破碎、飞溅、悬浮和反弹多种行为模式下的速度、粒径和角度，证明了涂层表面状态的差异性对于液滴撞壁行为有显著影响。根据试验结果，分别建立了两种涂层基于壁温与入射韦伯数We的液滴撞壁机制和数学模型，并结合化学反应动力学模型进行了燃烧传热分析，通过与OA模型仿真结果和真实发动机热试车测试数据的对比，验证了该模型具有更高的准确性。

关键词: 双组元发动机;涂层壁面;雾化液滴;撞壁试验;机制划分;建模