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针对飞行器高超声速飞行时严重的气动加热环境,设计一种层板对流冷却结构对翼前缘进行热防护.提出一种壁面冷却效率参数η,并运用流固耦合的分析方法,研究了对流冷却结构在特定条件下的冷却效果,其中采用水冷时头部冷却效率η值最低为0.25.研究表明,对流结构冷却效果与内部冷却槽道深宽比γ有重要关系,η值随γ的增大而增大至一个稳定值,此时冷却效果达到饱和,若此时γ继续增加则可能出现不利于冷却的现象.冷却效果η随着前缘头部半径的减小而减弱.研究还表明,当层板对流冷却结构和材料固定时,η值随冷却剂流量增加而增大,并逐渐趋近至一个稳定值,而冷却槽道进出口压差急剧增大.因此需要综合考虑提高流量给供给系统带来的压力,选取最佳流量值以达到相对较好的冷却效果.对于材料而言,内部冷却通道和外部耐热层都应选择导热系数较高的材料,能够强化结构传热增强冷却效果.
Aiming at severe aerodynamic heating environment during hypersonic flight, a kind of laminar convection cooling structure is designed to protect the wing from the leading edge.A wall cooling efficiency parameter η is proposed and the fluid-solid coupling analysis method is used to study the convection cooling The results show that the cooling effect of the convection structure has an important relation with the aspect ratio γ of the internal cooling channel, and the value of η increases with the increase of γ And increases to a stable value, at which point the cooling effect is saturated, and if γ continues to increase at this time, the phenomenon unfavorable to cooling may occur.The cooling effect η decreases with the decrease of the radius of the leading edge.The study also shows that, When the convective cooling structure and materials are fixed, the value of η increases with the increase of the coolant flow rate, and gradually approaches a stable value, while the pressure difference at the inlet and outlet of the cooling channel increases sharply, so we need to consider increasing the flow rate Supply system pressure, select the best flow value in order to achieve a relatively good cooling effect.For the material, the internal cooling channels and external heat-resistant layer should choose the material with higher thermal conductivity Material, can enhance the structure of heat transfer to enhance cooling effect.