Nozzle Throat Insert Material Ablation Of Experimental Research

New challenges were brought forward to nozzle thermal structure design, with the development of high energy aluminized propellant and the technological advancements of high pressure motor. At present, the primary problems in nozzle ablation research were as follows: lack of effective experimental instruments in particle erosion mechanism research, lack of enough knowledge on nozzle ablation rule at high pressure conditions, lack of experimental assessment at working conditions of motor for new type of thermal structure material. Experiments research were carried out for the throat of nozzle. Furthermore, an experimental method was developed for nozzle ablation, as made the adjusting of particle-flux under the working conditions of real motor available with other parameters constant. Nozzle ablation experiments using the method mentioned above were carried out, and the influence of particle-flux on the erosion-rate of nozzle was obtained. The relation between pressure and instantaneous linearity erosion rate was obtained through nozzle ablation experiments under high pressure. Other than, the ablation of ceramic matrix material was studied both in solid rocket motor and liquid rocket engine, and the relation between temperature and linearity erosion rate of ceramic matrix material was obtained.Results of the paper can be summarized as:(1) The linearity erosion rate of graphite reduces while particle mass flux decreases, with other parameter unaltered. The distributing of particle diameter affects erosion greatly. The decrease of large particles can weaken erosion.(2) The erosion of throat made of graphite, C/C and C/SiC has accumulate effect. The erosion -rates increase along with time.(3) The effect of pressure on graphite throat liner erosion is obvious at high pressure (9~20MPa). The erosion -rate increases while pressure increases. The relation between pressure and erosion rate can be calculated by pressure curve.(4) The erosion-rate of C/SiC increases with temperature .When temperature is above 2650K, it increase more quickly. The erosion of C/SiC in oxygen/ alcohol engine is more serious than in solid rocket engine.