摘要
该文针对发散冷却中由于结构本身的缺陷或者是局部大热流而引起的传热恶化问题,通过对烧结多孔壁面发散冷却过程进行数值模拟,对孔隙及热流的非均匀性对发散冷却壁面温度分布的影响进行了分析。结果表明:在一定的条件下,结构上的缺陷、堵塞或者局部大热流能引发局部高温,并发生冷却失效;恶化的扩散可导致发散冷却的失败;影响恶化的温度梯度的主要因素有多孔颗粒的材料、注入率、冷却剂以及壁面所承受的热量。该文针对局部高温或大热流所引发的冷却失效,提出了通过非均匀孔隙率及改变颗粒直径的办法来预防冷却失效的产生和扩散。
Transpiration cooling can fall due to structural defects or blockages that result in locally high heat fluxes. The paper presents a numerical study of the temperature non-uniformities caused by porosity and heat flux non-uniformities. The results show that the local wall temperature gradient rises rapidly because of the porosity and heat flux non-uniformltles in some cases, which may cause failure of the transpiration cooling. The particle material,the blowing ratio, the coolant, and the heat flux all influence the temperature gradient. Non-uniform porosities and particle diameter＇s can prevent failure of the transpiration cooling and the resulting locally high heat fluxes.
出处
《清华大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2006年第2期230-233,共4页
Journal of Tsinghua University(Science and Technology)
基金
国家杰出青年科学基金项目(50025617)
关键词
热工学
传热
发散冷却
多孔介质
冷却失效
pyrology
heat transfer
transpiration cooling
porous media
cooling failure
