检索结果-南通市图书馆

Recent progress in the study of transition in the hypersonic boundary layer

在线全文

学校读者我要写书评

暂无评论

National Science Review 2019年第1期6卷 155-170页

作者： cunbiao lee Shiyi Chen State Key Laboratory for Turbulence and Complex Systems Advanced Aero Engine Collaborative Innovation Center Peking University

Turbulence is a universal form of fluid motion. It is the key issue in fluid mechanics. Very recently, it has become a bottleneck in some key engineering research of national importance, such as aeronautics,astronautics and navigation. Developed turbulence and the onset of turbulence, i.e. transition, are two interrelated parts of turbulence. The hypersonic boundary-layer transition is a strategic focus in the fluid mechanics community. This article reviews recent developments in the study of the hypersonic boundary-layer transition, research facilities and experimental techniques. The hypersonic quiet wind tunnel is introduced as a necessary device to obtain real flight data in near space. Near-wall measurement techniques, such as temperature-sensitive paint, near-wall particle image velocimetry and Rayleigh-scattering visualization, are shown. The most important issues in the recent development of the transition in the hypersonic boundary layer are addressed. The instability and nonlinear interaction of different instability modes are discussed. The recent contributions from China, especially at Peking University, are also introduced.

关键词： hypersonic boundary layer transition quiet wind tunnel

Preface: symposium on turbulence structures and aerodynamic heat/force(STSAHF2018)——scientific significance of turbulence research

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2019年第2期40卷 181-184页

作者： cunbiao lee Zuoli XIAO Shiyi CHEN State Key Laboratory for Turbulence and Complex Systems Peking University Department of Aeronautics and Astronautics College of EngineeringPeking University Department of Mechanics and Engineering Science College of EngineeringPeking University Department of Mechanics and Aerospace Engineering South University of Science and Technology of China

Most fluid flows in nature and engineering applications are in the state of turbulence.Turbulent motions usually exhibit a wide range of spatial and temporal scales,such as the flow of natural gas and oil in pipelines,the wakes of cars and submarines,the boundary layer of an aircraft,the current in the ocean surface,the atmospheric boundary layer,the interstellar gas clouds(gaseous stars),and the Earth’s wake in the solar wind.Turbulence can greatly improve the heat and mass transfer efficiency of macroscopic flow.For example,chemical engineers use turbulence to mix up and homogenize fluid components and to increase chemical reaction rates in liquids or gases.However,turbulence can also lead to increases in drag,aerodynamic heat,and hydrodynamic and aerodynamic noise.For instance,the aerodynamic loading of high-speed aircraft can be significantly increased due to turbulence.

关键词： loading can Most cars drag gas mix be

Constrained large-eddy simulation and detached eddy simulation of flow past a commercial aircraft at 14 degrees angle of attack

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2013年第2期56卷 270-276页

作者： CHEN ShiYi CHEN YingChun XIA ZhenHua QU Kun SHI YiPeng XIAO ZuoLi LIU QiuHong CAI QingDong LIU Feng lee cunbiao ZHANG RiKui CAI JinSheng State Key Laboratory for Turbulence and Complex Systems and Center for Applied Physics and Technology College of EngineeringPeking University Shanghai Aircraft Design And Research Institute Commercial Aircraft Corporation of China Ltd. School of Aeronautics Northwestern Polytechnical University

With the development of computational power and numerical algorithms,computational fluid dynamics(CFD) has become an important strategy for the design of aircraft,which significantly reduces the reliance on wind-tunnel and flight tests.In this paper,we conducted a numerical investigation on the flow past a full commercial aircraft at Mach number 0.2 and 14 degrees angle of attack by means of Reynolds-averaged Navier-Stokes(RANS),detached-eddy simulation(DES) and our newly developed constrained large-eddy simulation(CLES).The objective of this paper is to study the capability of these models in simulating turbulent flows.To our knowledge,this is the first large-eddy simulation method for full commercial aircraft simulation.The results show that the CLES can predict the mean statistical quantities well,qualitatively consistent with traditional methods,and can capture more small-scale structures near the surface of the aircraft with massive separations.Our study demonstrates that CLES is a promising alternative for simulating real engineering turbulent flows.

关键词：大涡模拟方法商用飞机分离涡 Navier-Stokes 攻角商业计算流体动力学计算能力

在线全文

学校读者我要写书评

暂无评论

波纹壁面上的高超声速边界层气动降热

Science Bulletin 2022年第10期67卷 988-990页

作者：朱文凯顾丁炜司武飞陈十一朱一丁李存标 State Key Laboratory of Turbulence and Complex Systems Collaborative Innovation Center of Advanced Aero-EnginePeking UniversityBeijing 100871China

Hypersonic boundary layer transition is of fundamental importance for the design of high-speed vehicles because of its direct relevance to drag and aerodynamic heating.As the focus of transition and turbulence research is shifting towards higher velocities,research on compressible flows,especially hypersonic flows,is becoming increasingly attractive to researchers worldwide[1,2].

关键词： flows transition attractive

在线全文

学校读者我要写书评

暂无评论

开闸式异重流锋速转变的一个判据

中国科学：物理学、力学、天文学 2015年第3期45卷 41-47页

作者：彭明袁辉靖李存标北京大学工学院湍流与复杂系统研究国家重点实验室北京100871

异重流是两种流体因密度差异产生的流动,是自然和工业生产部门中常见的现象.开闸式异重流是异重流研究的常用和典型模型.本文利用时间解析粒子图像速度仪(TR-PIV)测量了水槽中的开闸式异重流流场.实验中观察到异重流传播过程中从锋速,... 详细信息

异重流是两种流体因密度差异产生的流动,是自然和工业生产部门中常见的现象.开闸式异重流是异重流研究的常用和典型模型.本文利用时间解析粒子图像速度仪(TR-PIV)测量了水槽中的开闸式异重流流场.实验中观察到异重流传播过程中从锋速,即头部速度为常数的初始坍塌阶段进入到锋速按时间的-1/3次幂递减的自相似阶段时,水平流速的速度剖面会发生振荡现象.该振荡是由开闸时传至左端壁而反射的波动引起的.这种振荡现象可作为开闸式异重流锋速转变的一个判据.

关键词：异重流粒子图像测速仪