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为开发有效的热防护技术,分别采用均匀青铜颗粒和不均匀青铜颗粒烧结而成的多孔板作为实验段,对平板发汗冷却进行了实验研究。实验结果表明:发汗冷却能有效地减少壁面和高温流体之间的换热;颗粒直径越小,相同条件下的冷却效果越好,但是需要的压降越大;在相同的压降下,不均匀颗粒多孔板中,直径大的一侧压阻小,相当于增大了注入率,因此壁温下降幅度更大。合适颗粒直径的选择与孔隙率、压降和强度的要求有关。
In order to develop effective thermal protection technology, porous plates sintered with uniform bronze particles and non-uniform bronze particles were respectively used as experimental sections to experimentally study the sweating and cooling of flat plates. The experimental results show that the sweat cooling can effectively reduce the heat transfer between the wall and the high-temperature fluid. The smaller the particle diameter, the better the cooling effect under the same conditions, but the larger the pressure drop required. Under the same pressure drop, In the uniform particle multi-well plate, the pressure resistance on the large diameter side is small, which is equivalent to increasing the injection rate, so that the wall temperature decreases more greatly. The choice of suitable particle diameter is related to the requirements of porosity, pressure drop and strength.