2O、CO2、H2）與表面碳發(fā)生的熱化學燒蝕；喉徑區(qū)換熱系數(shù)最大，溫度較高，內表面在應力作用下，燒蝕最為嚴重，為燃氣熱化學燒蝕、高速氣流機械剝蝕及粒子沖刷的共同作用，表面呈現(xiàn)出微小的溝槽或裂紋，應力與氧化使喉襯在低于材料極限應力下發(fā)生分解破壞；出口段應力降低，溫度明顯下降，燒蝕率顯著降低。喉襯燒蝕機理為溫度、應力影響下燃氣氧化組分與碳的熱化學燒蝕、氣流機械剝蝕和Al2O3顆粒侵蝕的聯(lián)合作用。;The heat transfer coefficient, temperature distribution, and stress distribution of 3D carbon/carbon (C/C) composite solid rocket motor (SRM) throat at the thermal equilibrium state were calculated through the comprehensive thermo-structural simulation, and SRM used the tri-component propellant of ammonium perchlorate/hydroxyl-terminated polybutadiene/Al under the condition of 6.5 MPa for long run of 20, 60, and 95 s. The analysis of ablation behavior and mechanism of different throat regions was also conducted according to the simulation results. The results show that the temperature at throat convergent zone is the highest due to the thermochemical ablation between the oxidation components (H2O, CO2, H2) and the surface carbon. The central throat zone has the maximum heat transfer coefficient with relatively high temperature. The ablation in the central throat zone is the most severe due to the stress of inner surface, including the gas thermochemical ablation, high-speed-flow mechanical denudation, and particle erosion. The central throat surface has small grooves or cracks, and the throat tends to decompose due to the stress and oxidation. The stress and temperature of throat exit zone are decreased, and the ablation rate is obviously reduced. The throat ablation mechanism is the combination effect of thermochemical ablation of oxidation components and the carbon influenced by the stress and temperature, flow mechanical denudation, and Al2O3 particle erosion."/>