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

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