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Oblique detonation wave triggered by a double wedge in hypersonic flow

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Chinese Journal of Aeronautics 2022年第4期35卷 176-184页

作者： honghui {1. Yuhang ZHANG Pengfei YANG zonglin jiang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China State key {1. of high temperature gas dynamics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering sci{1. University of Chinese Academy of SciencesBeijing 100049China

Pressure-gain combustion has gained attention for airbreathing ramjet engine applications owing to its better thermodynamic efficiency and fuel consumption rate. In contrast with traditional detonation induced by a single wedge, the present study considers oblique shock interactions attached to double wedges in a hypersonic combustible flow. The temperature/pressure increases sharply across the interaction zone that initiates an exothermic reaction, finally resulting in an Oblique Detonation Wave(ODW). Compared with the case for a single-wedge ODW, the double-wedge geometry has great potential to control the initiation of the ODW. As a tentative study, two-dimensional compressible Euler equations with a two-step induction-reaction kinetic model are used to solve the detonation {1. triggered by a double wedge. The effects of the wedge angles and wedge corner locations on the initiation structures are investigated *** results show an ODW complex comprising three Oblique Shock Waves(OSWs), an induction zone, a curved detonation front, and an unburned/low-temperature gas belt close to the surface of the second wedge. Both the increasing wedge angle and downstream wedge corner location lead to an abrupt OSW–ODW transition type, whereas the former corresponds to the shock–shock interaction and the later has a greater effect on the exothermic chemical process. Analysis of the shock polar and flow scale confirms that the OSW–ODW initiation structure mainly depends on the coupling of shocks and heat release in a confined initiation zone.

关键词： Double wedge Hypersonic flow Initiation structures Oblique detonation Shock interactions

Numerical investigation on detonation cell evolution in a channel with area-changing cross section

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science{1.(Physics,mechanics & Astronomy) 2007年第6期50卷 797-808页

作者： DENG Bo HU ZongMin teng {1. jiang zonglin key {1. of high temperature gas dynamics Institute of MechanicsChinese Academy of SciencesBeijing 100080China

The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Effects of the flow ex-pansion and compression on the cellular detonation cell were investigated to illus-trate the mechanism of the transverse wave development and the cellular detona-tion cell evolution. By examining gas composition variations behind the leading shock,the chemical reaction rate,the reaction zone length,and thermodynamic parameters,two kinds of the abnormal detonation waves were identified. To explore their development mechanism,chemical reactions,reflected shocks and rarefac-tion waves were discussed,which interact with each other and affect the cellular detonation in different ways.

关键词： detonation cells transverse waves detailed chemical reaction model numerical simulation

Reconstructing shock front of unstable detonations based on multi-layer perceptron

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Acta Mechanica Sinica 2021年第11期37卷 1610-1623,I0001页

作者： Lin Zhou honghui {1. Hoi Dick Ng Pengfei Yang zonglin jiang School of Aerospace Engineering Beijing Institute of TechnologyBeijing100081China State key {1. of Laser Propulsion and Application Beijing Power Machinery InstituteBeijing100074China Department of Mechanical Industrial and Aerospace EngineeringConcordia UniversityMontrealQCH3G 1M8Canada State key {1. of high temperature gas dynamics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering sci{1. University of Chinese Academy of SciencesBeijing100049China

The dynamics of frontal and transverse shocks in {1.eous detonation waves is a complex phenomenon bringing many difficulties to both numerical and experimental *** laser-optical visualization of detonation structure may provide certain information of its reactive front,but the corresponding lead shock needs to be reconstructed building the complete flow *** the multi-layer perceptron(MLP)approach,we propose a shock front reconstruction method which can predict evolution of the lead shock wavefront from the state of the reactive *** method is verified through the numerical results of one-and two-dimensional unstable detonations based on the reactive Euler equations with a one-step irreversible chemical reaction *** show that the accuracy of the proposed method depends on the activation energy of the reactive mixture,which influences prominently the cellular detonation instability and hence,the distortion of the lead shock *** select the input variables for training and evaluate their influence on the effectiveness of the proposed method,five groups,one with six variables,and the other with four variables,are tested and analyzed in the MLP *** trained MLP is tested in the cases with different activation energies,demonstrates the inspiring generalization *** paper offers a universal framework for predicting detonation frontal evolution and provides a novel way to interpret numerical and experimental results of detonation waves.

关键词： Cellular detonation Lead shock evolution Multi-layer perceptron Numerical simulations

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斜爆轰的多波结构及其稳定性研究进展

力学进展 2020年第1期50卷 50-92页

作者：滕宏辉姜宗林北京理工大学宇航学院北京100081 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 中国科学院大学工程科学学院宇航工程科学系北京100049

斜爆轰是气相爆轰物理的一个重要研究方向,在航空航天新型动力领域有重要的潜在应用价值.作为激波诱导的高速燃烧,斜爆轰波可以简化为包含能量添加的间断面.然而,斜爆轰流动中往往涉及激波、湍流等多种的流体力学现象,它们和燃烧放热耦... 详细信息

斜爆轰是气相爆轰物理的一个重要研究方向,在航空航天新型动力领域有重要的潜在应用价值.作为激波诱导的高速燃烧,斜爆轰波可以简化为包含能量添加的间断面.然而,斜爆轰流动中往往涉及激波、湍流等多种的流体力学现象,它们和燃烧放热耦合在一起,导致流动和燃烧机理非常复杂.一方面,斜爆轰波具有的多尺度和非线性的特征,理论研究难以深入;另一方面,爆轰波流场高温、高压、高速的特点,又给实验研究带来了很大的困难.过去20年,主要借助数值方法,研究者对斜爆轰波开展了系统的模拟和分析,在诸多方面取得了明显的进展.本文首先介绍了理想情况下的起爆区波系结构和波面稳定性研究进展;其次着眼于推进系统的问题,关注了非均匀来流效应以及斜爆轰波与稀疏波的作用;最后对未来的研究工作提出一些建议.

关键词：斜爆轰激波爆燃波起爆稳定性

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圆球诱发斜爆轰波的数值研究

力学学报 2017年第2期49卷 268-273页

作者：方宜申胡宗民滕宏辉姜宗林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 中国科学院大学工程科学学院北京100049

斜爆轰发动机是飞行器在高马赫数飞行条件下的一种新型发动机,具有结构简单、成本低和比冲高等优点.但是斜爆轰发动机的来流马赫数范围广,来流条件复杂,为实现斜爆轰波的迅速、可靠引发,采用钝头体来诱发.利用Euler方程和氢氧基元反应模... 详细信息

斜爆轰发动机是飞行器在高马赫数飞行条件下的一种新型发动机,具有结构简单、成本低和比冲高等优点.但是斜爆轰发动机的来流马赫数范围广,来流条件复杂,为实现斜爆轰波的迅速、可靠引发,采用钝头体来诱发.利用Euler方程和氢氧基元反应模型,对超声速氢气/空气混合气体中圆球诱导的斜爆轰流场进行了数值研究.不同于楔面诱发的斜爆轰波,球体首先会在驻点附近诱发正激波/爆轰波,然后在稀疏波作用下发展为斜激波/爆轰波.模拟结果显示,经过钝头体压缩的预混气体达到自燃温度后,会出现两种流场:当马赫数较低时,由于稀疏波的影响,燃烧熄灭,钝头体下游不会出现燃烧情况;而当马赫数较高时,燃烧阵面能传到下游.分析表明,当钝头体的尺度较小时,驻点附近的能量不足以诱发爆轰波,只会形成明显的燃烧带与激波非耦合结构;当钝头体的尺度较大时,流场中不会出现燃烧带与激波的非耦合现象,且这一特征与马赫数无关.通过调整球体直径,获得了激波和燃烧带部分耦合的燃烧流场结构,这一流场结构在楔面诱发的斜爆轰波中并不存在,说明稀疏波与爆轰波面的相互作用是决定圆球诱发斜爆轰波的关键.

关键词：斜爆轰氢氧起爆熄爆

Numerical Simulation of Deflagration to Detonation Transition in a StraightDuct: Effects of Energy Release and Detonation Stability

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Advances in Applied Mathematics and mechanics 2014年第6期6卷 718-731页

作者： Hua-Shu Dou Zongmin Hu Boo Cheong Khoo zonglin {1. Faculty of Mechanical Engineering and Automation Zhejiang Sci-Tech UniversityHangzhou 310018China State key {1. of high temperature gas dynamics Institute of MechanicsChinese Academy of SciencesBeijing 100080China Department of Mechanical Engineering National University of SingaporeSingapore 119260Singapore

Numerical simulation based on the Euler equation and one-step reaction model is carried out to investigate the process of deflagration to detonation transition(DDT)occurring in a straight *** numerical method used includes a high resolution fifth-order weighted essentially non-o{1.llatory(WENO)scheme for spatial discretization,coupled with a third order total variation diminishing Runge-Kutta time stepping *** particular,effect of energy release on the DDT process is *** model parameters used are the heat release at q=50,30,25,20,1.,1. and 5,the specific heat ratio at 1.2,and the activation temperature at Ti=1.,*** all the cases,the initial energy in the spark is about the same compared to the detonation energy at the Chapman-Jouguet(CJ)*** is found from the simulation that the DDT occurrence strongly depends on the magnitude of the energy *** run-up distance of DDT occurrence decreases with the increase of the energy release for q=5020,and increases with the increase of the energy release for q=20*** phenomenon is found to be in agreement with the analysis of mathematical stability *** is suggested that the factors to strengthen the DDT would make the detonation more stable,and vice ***,it is concluded from the simulations that the interaction of the shock wave and the flame front is the main reason for leading to DDT.

关键词： Numerical simulation detonation DDT energy release duct

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斜爆轰发动机的推力性能理论分析

力学学报 2021年第10期53卷 2853-2864页

作者：杨鹏飞张子健杨瑞鑫滕宏辉姜宗林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 中国科学院大学工程科学学院北京100049 香港理工大学航空与民航工程学系中国香港九龙999077 北京理工大学宇航学院北京100081

爆轰燃烧具有释热快、循环热效率高的特点.斜爆轰发动机利用斜爆轰波进行燃烧组织,在高超声速吸气式推进系统中具有重要地位.以往研究主要关注斜爆轰波的起爆、驻定以及波系结构等,缺少从整体层面出发对斜爆轰发动机开展推力性能分析.... 详细信息

爆轰燃烧具有释热快、循环热效率高的特点.斜爆轰发动机利用斜爆轰波进行燃烧组织,在高超声速吸气式推进系统中具有重要地位.以往研究主要关注斜爆轰波的起爆、驻定以及波系结构等,缺少从整体层面出发对斜爆轰发动机开展推力性能分析.本文将斜爆轰发动机内的流动和燃烧过程分解成进气压缩、燃料掺混、燃烧释热和排气膨胀4个基本模块并分别进行理论求解,建立了斜爆轰发动机推力性能的理论分析模型.在斜爆轰波系研究成果的基础上,选取了过驱动斜爆轰、Chapman-Jouguet斜爆轰、过驱动正爆轰和斜激波诱导等容燃烧等4种燃烧模式来描述燃烧室内的燃烧释热过程,并对比分析了不同燃烧模式对发动机比冲性能的影响.此外,还获得了不同来流参数、燃烧室参数和进排气参数等对发动机推力的影响规律,发现来流马赫数和尾喷管的膨胀面积比是发动机理论燃料比冲的主要影响因素.最后,结合以往关于受限空间内斜爆轰波驻定特性等方面的研究成果,提出了斜爆轰发动机燃烧室的设计方向.

关键词：斜爆轰波发动机推力性能燃烧模式