摘要
作为一种主动冷却方式,逆向喷流结构对高超声速飞行器的热防护具有显著效果。为了对头锥逆喷的防热特性进行准确预测,采用流热耦合方法,对6马赫下的头锥逆喷结构的流动和传热进行数值研究。通过数值计算和实验对比,验证了湍流模型和流热耦合算法的准确性,获得了不同逆喷总压比下的流动特性,并且对不同逆喷总压比对流动和传热的影响进行了分析。此外,讨论了攻角和固体材料对结构防热的效果影响。研究结果表明:逆喷总压比的提高使得气动加热降低,并且固体结构内的温度分布更加均匀;随着攻角的增大,经过60 s的热考核计算,结构内温差显著增大,导致逆喷冷空气进一步流向背风面,强化了背风面上的头部冷却效果;对于IN718和C-103两种不同材料,在头部冷气流回流区和再压缩激波影响显著的区域,气动加热的差异可以忽略,而采用C-103作为结构材料时结构内的温度分布更加均匀。
As one of the active cooling methods,the opposing jet shows its advantages on the aerodynamic thermal reduction for hypersonic flight.To accurately predict the thermal protection properties of the opposing jet,the numerical investigation on the flow and heat transfer characteristics for the opposing jet of nosecone at Mach 6 was conducted by using a fluid-thermal coupling strategy.The related turbulent model and fluid-thermal coupled method were validated by the comparison of the numerical and experimental results.Flow patterns of the opposing jet with different total pressure ratio were gained,and the influence of the total pressure ratio of the opposing jet on the heat transfer between fluid and solid structure was discussed.Besides,the influences of attack angle and solid materials on structural heat reduction were also investigated.The numerical results indicate that:the increase of total pressure ratio of the opposing jet brings obviously further heating reduction,and accordingly the solid structure temperature presents more uniformity;calculation of the heating in 60 s indicates that the positive attack angle enlarges the temperature difference in the solid structure,which induces the lower temperature air flowing to the leeward side furtherly,so the cooling for the leeward side of nosecone is enhanced;for alloy IN718 and C-103 two different materials,their discrepancy of heating can be neglected at the cooling recirculation region of nosecone and the area where the recompression shock influence obviously;in comparison,the use of C-103 shows its advantage of even distribution of temperature in the internal system of structure.
作者
尹亮
刘洪鹏
刘伟强
YIN Liang;LIU Hongpeng;LIU Weiqiang(College of Mechanical Engineering, Hunan University of Arts and Science, Changde 415000, China;College of Aerospace Science and Engineering, National University of Defense Technology, Changsha 410073, China)
出处
《国防科技大学学报》
EI
CAS
CSCD
北大核心
2022年第1期99-107,共9页
Journal of National University of Defense Technology
基金
湖南省教育厅科学研究资助项目(19C1271)
湖南文理学院博士启动基金资助项目(19BSQD25)。
关键词
高超声速
头锥
逆向喷流
流热耦合
热防护
hypersonic
nosecone
opposing jet
fluid-thermal coupling
thermal protection
