H. Genliang, S. Xunjia, Y. Xiaojing, Xi'an Research Institute of Hi-Tech, Xi’an, China
Based on the principle of the liquid-fueled rocket motor, the combustion model was proposed for the HVOF/HVAF system. The combustion gas components and temperature at different mixture fractions were analyzed. At lower oxygen content condition, the combustion temperature is lower and the solid content carbon content is higher. The whole fluent flow mode was proposed for the supersonic spray, which consists of the gas combustion,accelerating process,cooling process and decelerating process in the atmosphere. The velocity and temperature distributions were calculated according to this model, the results fitted well with the actual flame. The combustion gas parameters distributions are almost the same in the gun, but in the atmosphere the parameters have much difference. For HVOF, the under-expanded gas will expand in the atmosphere, while HVAF system is quite the contrary. At the gun exit,the combustion gas arrived supersonic both for the HVOF and HVAF condition. So the flame temperature and velocity can be adjusted for different values.
