The thermal performance prediction and development of ablator for reentry probes using a smallsat.

对轻量化烧蚀材料的研制和性能预测进行了研究。在加热开始时，气体平流引起的热流对换热起着重要的作用。烧蚀材料渗透率的变化对烧蚀材料的热响应有很大影响。对考虑热响应影响的鸟粪胶囊轻型烧蚀材料周围的流场进行了基于轨迹的数值模拟。热解气流将能量向后壁方向输送，使表观导热系数增大。重烧蚀与轻烧蚀的滞止热流密度相差很小。轻型烧蚀器的表面退缩是重型烧蚀器的几倍。因此，这项研究表明，轻质烧蚀材料不能使用相同的厚度，但它建议可以通过略微增加轻质烧蚀材料的厚度来防止发热。

It was performed that the development and a performance prediction of lightweight ablator. The beginning of heating, heat flux due to the gas advection plays an important role for heat transfer. The variation of permeability of the ablator is very effective on the thermal response of the ablator.A trajectory-based flow field simulation around Hayabusa capsule loaded lightweight ablator coupled with thermal response was carried out. The pyrolysis gas flow transport energies to the direction of rear wall and it makes the apparent heat conduction higher. The difference of stagnation heat flux between heavy ablator and lightweight ablator is very small. The surface recession of lightweight ablator is few times larger than heavy ablator. Therefore, this study shows lightweight ablator cannot use same thickness but it suggests that it can prevent heat by slightly increasing the thickness of the lightweight ablator.