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Extremely high wall pressure events in shock wave and turbulent boundary layer interactions using DNS data

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Chinese Journal of Aeronautics 2024年第11期37卷 81-93页

作者： Meijunjie LI xianxu yuan Siwei DONG Xinliang LI Fulin TONG State Key Laboratory of Aerodynamics Mianyang 621000China State Key Laboratory of High-Temperature Gas Dynamics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

This study investigates high-amplitude Extreme Wall Pressure fluctuation Events(EWPEs)in Shock wave/Turbulent Boundary Layer Interactions(STBLIs)through the conditional sampling of direct numerical simulation *** aim is to evaluate the effect of STBLIs and their strength on the statistical properties and associated turbulent structures of EWPEs using the conditional-averaging and clustering *** temporal statistical results show that the occurrence probability and contribution ratio of EWPEs decrease downstream of strong STBLI,but their duration and interval time *** two-dimensional wall pressure structures,the large population of small-scale structures becomes more elongated,but strong interactions induce a greater number of large-scale *** pairing of wall pressure events with a higher occurrence probability is verified by the joint probability density *** analysis reveals that,as the interaction strength increases,the ejection motion associated with positive events occurs farther downstream and the spanwise vortex core locating above negative events is lifted up along the wall-normal ***,analysis associates the paired wall pressure events with the sweep,ejection,and swirl motions in STBLIs,where hairpin eddies play an important role in the formation of positive-negative paired wall pressure structures.

关键词： Wall pressure fluctuations Extreme pressure events Shock wave Turbulent boundary layer Direct numerical simulation

Hypersonic shock wave and turbulent boundary layer interaction in a sharp cone/flare model

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Chinese Journal of Aeronautics 2023年第3期36卷 80-95页

作者： Fulin TONG Junyi DUAN Jiang LAI Dong SUN xianxu yuan State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China Computational Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China LHD Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

A direct numerical simulation of hypersonic Shock wave and Turbulent Boundary Layer Interaction(STBLI)at Mach 6.0 on a sharp ***-angle circular cone/flare configuration at zero angle of attack is *** flare angle is *** the momentum thickness Reynolds number based on the incoming turbulent boundary layer on the sharp circular cone is Re θ=*** is found that the mean flow is separated and the separation bubble occurring near the corner exhibits *** Reynolds analogy factor changes dramatically across the interaction,and varies between 1.06 and 1.27 in the downstream region,while the QP85 scaling factor has a nearly constant value of 0.5 across the *** evolution of the reattached boundary layer is characterized in terms of the mean profiles,the Reynolds stress components,the anisotropy tensor and the turbulence kinetic *** is argued that the recovery is incomplete and the near-wall asymptotic behavior does not occur for the hypersonic *** addition,mean skin friction decomposition in an axisymmetric turbulent boundary layer is carried out for the first *** of the interaction,the contributions of transverse curvature and body divergence are negligible,whereas the positive contribution associated with the turbulence kinetic energy production and the negative spatial-growth contribution are *** on scale decomposition,the positive contribution is further divided into terms with different spanwise length *** negative contribution is analyzed by comparing the convective term,the streamwise-heterogeneity term and the pressure gradient term.

关键词： Shock wave Hypersonic turbulent boundary layer Heat transfer Skin friction decomposition Direct numerical simulation

Predicting near-wall turbulence with minimal flow units in compressible turbulent channel flows

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Chinese Journal of Aeronautics 2023年第8期36卷 24-31页

作者： Ming YU Yalu FU Zhigong TANG xianxu yuan Chunxiao XU State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China Key Laboratory of Applied Mechanics of Ministry of Education Institute of Fluid MechanicsDepartment of Engineering MechanicsTsinghua UniversityBeijing 100084China

Mach number effects on the near-wall turbulence in the absence of outer motions remain unclear so *** present study extends the Minimal Flow Units(MFUs),a widely applied method to investigate near-wall turbulence free from the impact of large-scale motions in the outer region in incompressible channel flows,to compressible wall-bounded *** compressible near-wall turbulence in MFU proves accurate in replicating near-wall statistics,independent of Mach number and statistically equivalent to the universal signals extracted from the full-sized *** is further utilized as universal signals in the predictive models of compressible near-wall turbulence,which is capable of accurately predicting variances and joint probability density functions of velocity and temperature fluctuations.

关键词： Turbulent flow Direct numerical simulation Supersonic flow Boundarylayerflow Mach number effects

Effect of gas blowing on the head of thermal ablation vehicle

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Advances in Aerodynamics 2022年第1期4卷 188-202页

作者： Qing Li xianxu yuan Jianqiang Chen Lin Bi State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang621000China Computational Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang621000China

The reentry vehicle will encounter thermal ablation,especially at the stagnation point regime.A theoretical work has been done to analyze the thermal effect of gas blowing due to thermal ablation of surface material on the head of a general hypersonic *** deriving the formulation,research takes into account the effect of gas blowing on the thermal dynamics balance,and then solves them by numerical *** is found that gas blowing will increase the temperature and heat flux at the surface of stagnation point regime.

关键词： Stagnation point flow Viscous compression of fluid parcel Gas blowing

On the Characteristic Length Scale for the Synthetic Turbulence Based on the Spalart-Allmaras Model

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Advances in Applied Mathematics and Mechanics 2024年第1期16卷 122-145页

作者： Qilong Guo Pengxin Liu Chen Li Dong Sun xianxu yuan State Key Laboratory of Aerodynamics MianyangSichuan 621000China

In the hybrid RANS-LES simulations,proper turbulent fluctuations should be added at the RANS-to-LES interface to drive the numerical solution restoring to a physically resolved turbulence as rapidly as *** turbulence generation methods mostly need to know the distribution of the characteristic length scale of the background RANS model,which is important for the recovery *** approximation of the length scale for the Spalart-Allmaras(S-A)model is not a trivial issue since the model’s one-equation *** a direct analogy,the approximations could be obtained from the definition of the Prandtl’s mixing ***,this paper proposes a new algebraic expression to approximate the intrinsic length scale of the S-A *** underlying transportation mechanism of S-A model are largely exploited in the derivation of this new *** new proposed expression is employed in the generation of synthetic turbulence to perform the hybrid RANS-LES simulation of canonical wall-bounded turbulent *** comparisons demonstrated the feasibility and improved performance of the new length scale on generating synthetic turbulence at the LES inlet.

关键词： Length scale synthetic turbulence hybrid RANS-LES Spalart-Allmaras model

Experimental study of bluntness effects on hypersonic boundary-layer transition over a slender cone using surface mounted pressure sensors

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Advances in Aerodynamics 2022年第1期4卷 743-761页

作者： Ranran Huang Jiangyi Cheng Jianqiang Chen xianxu yuan Jie Wu School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan430074People’s Republic of China State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang621000People’s Republic of China Computational Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang621000People’s Republic of China

In this work,we studied the bluntness effect on the hypersonic boundary-layer transition over a slender cone at Mach 6 with interchangeable tips in a noisy Ludwieg tube tunnel before the so-called“transition reversal”phenomenon *** evolution of instability waves is characterized using surface flush-mounted pressure sensors deployed along the streamwise direction within unit Reynolds number from 4E+6/m≤Reunit≤10E+6/m,and the bluntness of the cone nose ranges from 0.1 mm to 5 *** spectral density(PSD)of pressure fluctuation indicates that small nose bluntness(ReR≤2000)has little influence on the evolution of instability waves along the hypersonic boundary-layer,whereas with a moderate nose size(2000≤ReR≤5000),the hypersonic boundary layer transition is delayed monotonically as the nose radius increases before the boundary-layer turns into fully laminar without instability *** delaying effect can be attributed to the increased entropy-layer swallowing distance with a large tip *** wave characterization reveals that the second mode instability wave plays a dominant role before the transition reversal *** quadratic phase locking of second mode instabilities can be identified by bispectral analysis,and it attenuates as the nose tip radius increases.

关键词： Hypersonic boundary-layer Laminar/turbulent boundary-layer transition Bluntness effect Second mode

A decomposition formula for the wall heat flux of a compressible boundary layer

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Advances in Aerodynamics 2021年第1期3卷 597-609页

作者： Dong Sun Qilong Guo xianxu yuan Haoyuan Zhang Chen Li Pengxin Liu State Key Laboratory of Aerodynamics Mianyang 621000SichuanChina Computational Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000SichuanChina

Understanding the generation mechanism of the heat flux is essential for the design of hypersonic *** proposed a novel formula to decompose the heat flux coefficient into the contributions of different terms by integrating the conservative equation of the total *** reliability of the formula is well demonstrated by the direct numerical simulation results of a hypersonic transitional boundary *** this formula,the exact process of the energy transport in the boundary layer can be explained and the dominant contributors to the heat flux can be explored,which are beneficial for the prediction of the heat and design of the thermal protection devices.

关键词： Heat flux Hypersonic boundary layer Direct numerical simulation

Design and transition characteristics of a standard model for hypersonic boundary layer transition research

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Acta Mechanica Sinica 2021年第11期37卷 1637-1647,I0002页

作者： Shenshen Liu xianxu yuan Zhiyong Liu Qiang Yang Guohua Tu Xi Chen Yewei Gui Jianqiang Chen State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang621000China Computational Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang621000China China Academy of Aerospace Aerodynamics Beijing100074China

To understand fundamental problems in hypersonic laminar-turbulent boundary layer transition for three-dimensional complex vehicles,a new standard model with typical lifting-body features has been proposed,named as hypersonic transition research vehicle(HyTRV).The configuration of HyTRV is fully analytical,and details of the design process are discussed in this *** transition characteristics for HyTRV are investigated using three combined methods,i.e.,theoretical analyses,numerical simulations,and wind tunnel *** show that the fully analytic parameterization design of HyTRV can satisfy the model simplification requirements from both numerical simulations and wind tunnel ***,the flow field of HyTRV reveals typical transition mechanisms in six relatively separated regions,including the streamwise vortex instability,crossflow instability,secondary instability,and attachment-line ***,the proposed HyTRV model is valuable for fundamental researches in hypersonic boundary layer transition.

关键词： Hypersonic boundary layer Transition research Standard model design HyTRV

Progress in flight tests of hypersonic boundary layer transition

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Acta Mechanica Sinica 2021年第11期37卷 1589-1609,I0001页

作者： Guohua Tu Jianqiang Chen xianxu yuan Qingtao Yang Maochang Duan Qiang Yang Yi Duan Xi Chen Bingbing Wan Xinghao Xiang State Key Laboratory of Aerodynamics China Aerodynamics Research&Development CenterMianyang621000China Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang621000China Science and Technology on Space Physics Laboratory China Academy of Launch Vehicle TechnologyBeijing100076China

Boundary layer transition(BLT)can cause a sharp rise in heat flux and skin friction,which can seriously affect the flight performance and safety of hypersonic flight ***,the mechanism,prediction and control of transition have become important issues that must be dealt with for the development of advanced flight vehicles,and it is also a research hotspot of particular interest to major aerospace *** to other transition research approaches,model flight tests can better present the transition problems under real flight conditions,thus have been carried out extensively over the past 30 *** United States,Germany,France,Australia,and other countries have carried out transition research based on flight tests,such as the Pegasus wing-glove crossflow transition and the Hypersonic Boundary Layer Transition(HyBOLT)transition control flight test of the United States,the joint research project of the Hypersonic International Flight Research and Experimentation-1(HIFiRE-1)circular cone and the HIFiRE-5 elliptic cone transition flight tests between the United States and Australia,the flight test of compression surface transition of the scramjet forebody(LEA)in France and so *** these flight tests suffered various setbacks,they still obtained valuable transition ***,the United States is carrying out the concave-surface transition flight tests of Hypersonic Boundary Layer Transition(BOLT)and *** its first model flight test mission for verification purpose launched successfully in 2015,several hypersonic BLT flight tests have been conducted by China Aerodynamics Research and Development Center(CARDC).The flight tests have measured valid transition data under flight conditions,obtained the transition front and its dynamical variation on blunt cones at various angles of attack and a lifting body Hypersonic Transition Research Vehicle(HyTRV).The crossflow traveling waves in high-altitude flight were measured for the first t

关键词： Hypersonic flow Boundary layer transition Flight test MF-1 HyTRV