Abstract: Based on the ablation situation of aerogel quartz fiber felt at high temperatures, considering the processes such as heat capacity heat absorption, thermal decomposition heat absorption and heat dissipation from the escape of thermal decomposition gas of aerogel, a heat transfer simulation mathematical model of it under 1 000 ℃ high-temperature ablation was established, and it was verified by the Muffle furnace ablation experiment. The temperature distribution inside the aerogel quartz fiber felt, the temperature changes on the back of the fabric under different ablation modes, and the insulation contribution of aerogel to quartz fibers were predicted respectively by the heat transfer model. The results show that the back temperature of the aerogel quartz fiber felt predicted by the numerical model is very close to the experimental data, with an average relative error of 2.8%. By adopting the slow heating mode of heating from room temperature at a rate of 10 ℃/min to 1 000 ℃ and ablating for 1 500 s, when the fiber felt reached thermal equilibrium, the back temperature of the 25 mm thick aerogel fiber felt was finally 201.4 ℃, which was lower than the back temperature of 210.1 ℃ when directly heated at 1 000 ℃. They are all lower than the back temperature of the quartz fiber felt of the same specification without impregnation with aerogel, which is 215.4 ℃.

Key words: aerogel, quartz fiber felt, pyrolysis, heat transfer simulation, heating mode