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Prediction of separation flows around a 6:1 prolate spheroid using RANS/LES hybrid approaches

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Acta Mechanica Sinica 2007年第4期23卷 369-382页

作者： zhixiang xiao Yufei Zhang Jingbo Huang Haixin Chen song fu school of aerospace engineering,tsinghua university,beijing 100084,china school of aerospace engineering Tsinghua University Beijing China

This paper presents hybrid Reynolds-averaged Navier-Stokes （RANS） and large-eddy-simulation （LES） methods for the separated flows at high angles of attack around a 6：1 prolate spheroid. The RANS/LES hybrid meth- ods studied in this work include the detached eddy simulation （DES） based on Spalart-Allmaras （S-A）, Menter＇s k-ω shear-stress-transport （SST） and k-o9 with weakly nonlinear eddy viscosity formulation （Wilcox-Durbin＋, WD＋） models and the zonalANS/LES methods based on the SST and WD＋ models. The switch from RANS near the wall to LES in the core flow region is smooth through the implementation of a flow-dependent blending function for the zonal hybrid method. All the hybrid methods are designed to have a RANS mode for the attached flows and have a LES behavior for the separated flows. The main objective of this paper is to apply the hybrid methods for the high Reynolds number separated flows around prolate spheroid at high-incidences. A fourth-order central scheme with fourth-order artificial viscosity is applied for spatial differencing. The fully implicit lower-upper symmetric-Gauss-Seidel with pseudo time sub-iteration is taken as the temporal differentiation. Comparisons with available measurements are carried out for pressure distribution, skin friction, and profiles of velocity, etc. Reasonable agreement with the experiments, accounting for the effect on grids and fundamental turbulence models, is obtained for the separation flows.

关键词： RANS/LES hybrid methods DES Zonal-RANS/LES Weakly nonlinear correction

Study of control effects of vortex generators on a supercritical wing

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Science china(Technological Sciences) 2010年第8期53卷 2038-2048页

作者： HUANG JingBo 1 ,xiao zhixiang 1 ,fu song 1 &ZHANG Miao 2 1 school of aerospace engineering,tsinghua university,beijing 100084,china 2 Shanghai Aircraft Design and Research Institute of COMAC,Shanghai 200232,china school of aerospace engineering Tsinghua University Beijing China Shanghai Aircraft Design and Research Institute of COMAC Shanghai China

Flows around vortex generators(VGs),which serve as one of the important flow control methods,are investigated by solving Reynolds-averaged Navier-Stokes(RANS)*** influences on the main flow of VGs are intended to ***, the flow around a single VG on a flat plane is computed to validate the schemes and to acquire basic knowledge of this kind of ***,transonic flow past a standard model,named by ONERA-M6 wing,is predicted to investigate the flow features of shockwave/boundary-layer interactions(SWBLI).Thirdly,the effects of a row of VGs mounted about 25%local chord on a supercritical wing are analyzed in transonic condition with strong ***,VGs are mounted more upwind(about 3.5%local chord)to explore the effects at low speed and high incidence *** numerical results show that seven VGs can effectively suppress the separations behind the strong SWBLI and decrease spanwise flow and wing-tip vortex in transonic *** also can decrease the large scope of separation over the wing at low speed with high angle of attack.

关键词： supercritical wing vortex generator(VG) shockwave/boundary-layer interactions(SWBLI)

Secondary instability control of compressible flow by suction for a swept wing

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Science china(Physics,Mechanics & Astronomy) 2011年第11期54卷 2040-2052页

作者： XU GuoLiang xiao zhixiang fu song school of aerospace Tsinghua University Beijing 100084 China

The crossflow instability of a three-dimensional boundary layer is a main factor affecting the transition around the *** three-dimensional boundary layer flow affected by the saturated crossflow vortex is very sensitive to the high frequency disturbances,which foreshadows that the swept wing flow transition will *** primary instability of the compressible flow over a swept wing is investigated with nonlinear parabolized stability equations (NPSE).The Floquet theory is then applied to the analysis of the influence of localized steady suction on the secondary instability of crossflow *** results show that suction can significantly suppress the growth of the crossflow mode as well as the secondary instability modes.

关键词： boundary layer suction crossflow instability secondary instability

Analysis of the secondary instability of the incompressible flows over a swept wing

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Science china(Physics,Mechanics & Astronomy) 2011年第4期54卷 724-736页

作者： XU GuoLiang xiao zhixiang fu song school of aerospace engineering Tsinghua University Beijing 100084 China

The crossflow instability of a three-dimensional (3-D) boundary layer is an important factor which affects the transition over a *** this report,the primary instability of the incompressible flow over a swept wing is investigated by solving nonlinear parabolized stability equations (NPSE).The Floquet theory is applied to study the dependence of the secondary and high-frequency instabilities on curvature,Reynolds number and angle of swept (AOS).The computational results show that the curvature in the present case has no significant effect on the secondary *** is generally believed that the secondary instability growth rate increases with the magnitude of the nonlinear mode of crossflow ***,at a certain state,when the Reynolds number is 3.2 million,we find that the secondary instability growth rate becomes smaller even when the magnitude of the nonlinear mode of the crossflow vortex is *** effect of the angle of swept at 35,45 and 55 degrees,respectively,is also studied in the framework of the secondary linear stability *** angles of swept tend to decrease the spanwise spacing of the crossflow vortices,which correspondingly helps the stimulation of 'z' mode.

关键词： crossflow instability secondary instability curvature angle of swept

Simulation of shock wave buffet and its suppression on an OAT15A supercritical airfoil by IDDES

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Science china(Physics,Mechanics & Astronomy) 2012年第2期55卷 260-271页

作者： HUANG JingBo xiao zhixiang LIU Jian fu song school of aerospace engineering Tsinghua UniversityBeijing 100084China china Aerodynamics Research&Development Center Mianyang 621000China

In the present paper,extremely unsteady shock wave buffet induced by strong shock wave/boundary-layer interactions (SWBLI) on the upper surface of an OAT15A supercritical airfoil at Mach number of 0.73 and angle of attack of 3.5 degrees is first numerically simulated by IDDES,one of the most advanced RANS/LES hybrid *** results imply that conventional URANS methods are unable to effectively predict the buffet phenomenon on the wing surface;IDDES,which involves more flow physics,predicted buffet *** complex flow phenomena are predicted and demonstrated,such as periodical oscillations of shock wave in the streamwise direction,strong shear layer detached from the shock wave due to SWBLI and plenty of small scale structures broken down by the shear layer instability and in the *** root mean square (RMS) of fluctuating pressure coefficients and streamwise range of shock wave oscillation reasonably agree with experimental ***,two vortex generators (VG) both with an inclination angle of 30 degrees to the main flow directions are mounted in front of the shock wave region on the upper surface to suppress shock wave *** results show that shock wave buffet can be significantly suppressed by VGs,the RMS level of pressure in the buffet region is effectively reduced,and averaged shock wave position is obviously pushed downstream,resulting in increased total lift.

关键词： supercritical airfoil vortex generator shock wave buffet

Direct numerical simulation of hypersonic transition induced by an isolated cylindrical roughness element

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Science china(Physics,Mechanics & Astronomy) 2014年第12期57卷 2330-2345页

作者： DUAN Zhi Wei xiao Zhi Xiang fu song school of aerospace Tsinghua University

Hypersonic boundary layer transition induced by an isolated cylindrical roughness element is investigated using direct numerical simulation method based on a finite volume *** simulate the transition procedure by resolving the generation and evolvement of small-scale coherent structures,and capture the shock wave at the same time,high-order minimum dispersion and controllable dissipation scheme is validated and then *** results are compared with the available measurements in the quiet wind tunnel,such as the dominated frequency and root mean square of *** computational dominated frequency of 19.23 k Hz is very close to the experimental one,21 k ***,the disturbances of the roughness are mostly generated by the"jet"just before the roughness,and then they travel and develop downstream with the shear layer and vortex *** transition is mainly dominated by the instabilities of both the horseshoe vortex and the shear layer.

关键词： hypersonic boundarry layer transtion roughness

Numerical simulation shock wave buffet on an OAT15A airfoil by IDDES hybrid methods

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Numerical simulation shock wave buffet on an OAT15A airfoil ...

使用IDDES方法预测飞行速度对喷流噪声的影响

23rd International Congress of Theoretical and Applied Mechanics

作者： Jingbo Huang zhixiang xiao Jian Liu song fu school of aerospace engineering Tsinghua University china Aerodynamics Research and Development Center

＜正＞Unsteady shock wave buffet phenomenon on the upper surface of supercritical airfoils is predicted by IDDES hybrid *** geometry is an OAT15A airfoil at Mach number of 0.73 and angle of attack of 3.5°***-adaptive...

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空气动力学学报 2018年第3期36卷 463-469页

作者：朱文庆肖志祥符松清华大学航天航空学院北京100084

使用变网格尺度定义的IDDES方法,预测了飞行速度对喷流噪声的影响。分析具有试验数据的喷流状态(Ma=0.9,基于喷管直径D的Re_D=1.1×10~6),通过与试验结果的对比,验证方法的正确性,并做了网格敏感性分析,对比了不同FW-H方程积分面对结果... 详细信息

使用变网格尺度定义的IDDES方法,预测了飞行速度对喷流噪声的影响。分析具有试验数据的喷流状态(Ma=0.9,基于喷管直径D的Re_D=1.1×10~6),通过与试验结果的对比,验证方法的正确性,并做了网格敏感性分析,对比了不同FW-H方程积分面对结果的影响。增加自由来流马赫数会增加喷流势流核的长度,降低势流核结束位置的湍动能,降低远场噪声辐射。对远场噪声的影响规律与试验测量值相符,说明此方法适用于存在飞行速度的喷流噪声问题的预测。

关键词：喷流噪声 IDDES方法灰区 FW-H积分面飞行速度

Progress in ceramic materials and structure design toward advanced thermal barrier coatings

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Journal of Advanced Ceramics 2022年第7期11卷 985-1068页

作者： Zhi-Yuan WEI Guo-Hui MENG Lin CHEN Guang-Rong LI Mei-Jun LIU Wei-Xu ZHANG Li-Na ZHAO Qiang ZHANG xiao-Dong ZHANG Chun-Lei WAN Zhi-Xue QU Lin CHEN Jing FENG Ling LIU Hui DONG Ze-Bin BAO xiao-Feng ZHAO xiao-Feng ZHANG Lei GUO Liang WANG Bo CHENG Wei-Wei ZHANG Peng-Yun XU Guan-Jun YANG Hong-Neng CAI Hong CUI You WANG fu-Xing YE Zhuang MA Wei PAN Min LIU Ke-song ZHOU Chang-Jiu LI State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory for Strength and Vibration of Mechanical Structures Department of Engineering MechanicsSchool of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an aerospace Composite Research Institute Xi’an 710025China AECC beijing Institute of Aeronautical Materials Beijing 100095China school of Materials Science and engineering Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of New Ceramics&Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaFaculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Faculty of Materials Science and engineering Kunming University of Science and TechnologyKunming 650093China school of Materials Science and engineering Beijing Institute of TechnologyBeijing 100081China Xi’an Key Laboratory of High Performance Oil and Gas Field Materials School of Materials Science and EngineeringXi’an Shiyou UniversityXi’an 710065China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming Shanghai Jiao Tong UniversityShanghai 200240China National engineering Laboratory for Modern Materials Surface engineering Technology the Key Lab of Guangdong for Modern Surface Engineering TechnologyInstitute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China school of Materials Science and engineering Tianjin UniversityTianjin 300072China Integrated Computational Materials Research Centre Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China State Key Laboratory of Advanced Processing and Recycling of

Thermal barrier coatings(TBCs)can effectively protect the alloy substrate of hot components in aeroengines or land-based gas turbines by the thermal insulation and corrosion/erosion resistance of the ceramic top ***,the continuous pursuit of a higher operating temperature leads to degradation,delamination,and premature failure of the top *** new ceramic materials and new coating structures must be developed to meet the demand for future advanced TBC *** this paper,the latest progress of some new ceramic materials is first ***,a comprehensive spalling mechanism of the ceramic top coat is summarized to understand the dependence of lifetime on various factors such as oxidation scale growth,ceramic sintering,erosion,and calcium–magnesium–aluminium–silicate(CMAS)molten salt ***,new structural design methods for high-performance TBCs are discussed from the perspectives of lamellar,columnar,and nanostructure *** latest developments of ceramic top coat will be presented in terms of material selection,structural design,and failure mechanism,and the comprehensive guidance will be provided for the development of next-generation advanced TBCs with higher temperature resistance,better thermal insulation,and longer lifetime.

关键词： thermal barrier coatings(TBCs) ceramic material degradation and failure structure design long lifetime