高马赫数燃烧强化的激波风洞试验研究  

SHOCK-TUNNEL EXPERIMENTAL STUDY OF COMBUSTION ENHANCEMENT METHODS FOR A HIGH-MACH-NUMBER SCRAMJET

作　　者：张旭[1,2] 张启帆 岳连捷 孟东东[1] 罗苇航 于江鹏 张晓源 李进平 陈宏[1,2] 李飞[1,2] Zhang Xu;Zhang Qifan;Yue Lianjie;Meng Dongdong;Luo Weihang;Yu Jiangpeng;Zhang Xiaoyuan;Li Jinping;Chen Hong;Li Fei(State Key Laboratory of High Temperature Gas Dynamics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China;School of Engineering Science,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院力学研究所高温气体动力学国家重点实验室,北京100190 [2]中国科学院大学工程科学学院,北京100049

出　　处：《力学学报》2022年第5期1403-1413,共11页Chinese Journal of Theoretical and Applied Mechanics

基　　金：国家自然科学基金(U2141220,11902325)资助项目。

摘　　要：基于中国科学院力学研究所的JF-24激波风洞,通过开展高马赫数超燃冲压发动机的直连试验,研究了高马赫数燃烧的强化方法以及燃料类型对燃烧的影响.试验段是采用凹腔结构的圆截面燃烧室,喷孔布置在隔离段,燃料分别是氢气和乙烯,当量比均为0.7.燃料喷注分别采用无支板和小支板两种构型,后者部分喷孔位于小支板顶部.两种构型均设置了流向近距双排喷孔,可分别进行单环和双环喷注.试验结果论证了飞行马赫数10.0条件下氢气和乙烯在超高速气流中的稳定燃烧性能.并且,相比于单环喷注,双环喷注以及补充小支板可以强化燃烧.推测其原因是双环射流和激波/分离结构的近距离交互作用很可能改善掺混,而补充小支板顶部喷注还能利用更多空气组织掺混.在同样采用双环耦合小支板顶部喷注的强化措施下,氢气与乙烯燃烧效率接近,但氢推力性能更优.这是因为较高热值氢的释热更多.此外,试验还证明了在当前来流条件下,释热受控于掺混,且高温离解效应限制释热上限.这是由于释热降低流速且提高静温,使高温离解的吸热效应更加显著.Based on the JF-24 high-enthalpy shock tunnel in Institute of Mechanics,Chinese Academy of Sciences,the current paper performed direct-connect combustion tests of a high-Mach-number scramjet engine to study highMach-number combustion enhancement methods and fuel types’effects.The test-section was a circular cross-section scramjet combustor with cavity structures,and fuel injectors were arranged in the isolator.Hydrogen and ethylene fuels were severally used in current tests at the same equivalence ratio of 0.7.Fuel injection utilized two different test-section configurations without and with small struts,respectively.Some injection holes of the latter configuration were located on the strut tops.For each configuration,two adjacent rings of injecting holes were arranged for single-ring and dualrings injections,respectively.Test results demonstrated that stabilized combustion performances of hydrogen and ethylene fuels in hypersonic flows under a Mach number Maf=10flight condition.Meanwhile,compared to the singlering fuel injection method,dual-rings fuel injections and adding injections on small-strut tops were beneficial for combustion enhancements.The reason was speculated that interactions of adjacent fuel jets and shock/separation structures probably could improve fuel-air mixing,and additional fuel injection on small-strut tops meant more available air for mixing.Under the same combustion enhancement methods of dual-ring injections and additional small-strut top injections,hydrogen fuel generated better thrust performance than ethylene fuel,while their combustion efficiencies were similar.This was possibly because that the hydrogen fuel had a higher caloricity,and thus it could generate more heat release.Besides,test also verified that under the current high-enthalpy high-speed inflow condition,combustion heat release was controlled by fuel-air mixing processes,and meanwhile the upper limits of heat release was limited by hightemperature dissociation effects.This was because that heat release led to decrease

关 键 词：高马赫数 超声速燃烧 燃烧强化 小支板 JF-24激波风洞 

分 类 号：O35[理学—流体力学]