Analysis and optimization design of thermal insulation performance of aerogel structures with thermal conductive layers

To enhance the thermal insulation performance of aerogel-based thermal protection structures under localized hightemperature heating, a thermal dredging design scheme was proposed, which involves embedding a boron nitride thermally conductive layer within the aerogel. This design improves the in-plane heat diffusion, expands the effective area for heat transfer and absorption, reduces the through-thickness heat flux into the cabin, lowers the inner wall temperature of the thermal protection structure, and ultimately improves the overall thermal insulation performance. A finite element analysis methodology was established to evaluate thermal insulation performance and was validated through a cavity heat transfer test. Using this numerical approach, the influence of the thermally conductive layer on the temperature field distribution and heat flow transmission in the aerogel thermal protection structure was investigated, and the optimal placement of the conductive layer was determined. The results demonstrate that incorporating the thermally conductive layer can reduce the inner wall temperature of the insulation structure by 52.6%, and under unchanged inner wall temperature criteria, the aerogel weight can be reduced by 14%.