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

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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 *** 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 *** can greatly improve the heat and mass transfer efficiency of macroscopic *** example,chemical engineers use turbulence to mix up and homogenize fluid components and to increase chemical reaction rates in liquids or ***,turbulence can also lead to increases in drag,aerodynamic heat,and hydrodynamic and aerodynamic *** 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

Generation of acoustic waves in the hypersonic boundary layer over a wavy wall

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Science China(Physics,Mechanics & Astronomy) 2022年第3期65卷 62-70页

作者： WenKai Zhu DingWei Gu YiDing Zhu cunbiao lee State KeyLaboratory of Turbulence and Complex Systems Collaborative Innovation Center of Advanced Aero-EnginePeking UniversityBeijing 100871China

The effects of a wavy wall on a hypersonic boundary layer of a flared cone are investigated using experimental measurements and direct numerical simulations(DNSs). Non-contact optical measurements using a focused laser differential interferometer(FLDI) show that a wavy wall can significantly suppress the second mode, and multiple perturbations of new frequencies are generated over the wavy surface, which agrees well with numerical results. Using Lagrangian tracking of marked particles, it is demonstrated that the wavy wall geometry can induce mean flow oscillations while exciting acoustic waves. The frequencies of the excited disturbances over a wavy wall agree with the classical Rossiter model. The superposition of a disturbance propagating downstream and an acoustic wave propagating upstream at the same frequency but with different amplitudes and propagation velocities results in a spatial distribution with a streamwise-oscillatory pattern over the wavy surface. A simple two-wave superposition model that takes into account the phase velocities and wavenumbers of the convective disturbance and acoustic wave can well describe the modal behavior of excited disturbances over a wavy wall.

关键词： instability of boundary layers compressible flows hypersonic flows

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

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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 *** 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 *** our knowledge,this is the first large-eddy simulation method for full commercial aircraft *** 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 *** study demonstrates that CLES is a promising alternative for simulating real engineering turbulent flows.

关键词： turbulence simulation Reynolds-averaged Navier-Stokes (RANS) detached-eddy simulation (DES) constrained large-eddysimulation (CLES) full-aircraft simulation

Reduced aerodynamic heating in a hypersonic boundary layer by a wavy wall

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

作者： Wenkai Zhu Dingwei Gu Wufei Si Shiyi Chen Yiding Zhu cunbiao lee 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 *** 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

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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

Research and development of the longitudinal feedback system digital signal processing electronics in BEPCII

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Radiation Detection Technology and Methods 2021年第2期5卷 213-219页

作者： Di Yin Junhui Yue Huizhou Ma Jianshe Cao Shujun Wei cunbiao Hao Yanfeng Sui Jun He Jingxia Zhao Zhi Liu Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049People’s Republic of China 2 Accelerator Technology and Key Laboratory of Academy of Physics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049People’s Republic of China University of Chinese Academy Sciences Beijing 100049People’s Republic of China

Background The current strategy to achieve high luminosity for high energy physics experiments is to store huge currents distributed in many bunches in circular machines such as BEPCII,so the longitudinal coupled bunch instabilities of the beam are *** Therefore,a longitudinal feedback system is needed to suppress longitudinal ***,the beam energy spread will increase;the luminosity and the beam lifetime will decrease under a certain beam *** For filter design of the feedback system,the time domain least square fitting(TDLSF)method is compared to the selective wave filter method;digital signal processing electronics based on commercial board have been developed and tested on *** The final result shows that the self-developed longitudinal feedback system can suppress the longitudinal beam oscillation at 750 mA beam current and meet the requirements of BEPCII;the restrain depth to the sidebands reaches to 40.8 dB.

关键词： Longitudinal bunch instability BEPCII Feedback system

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高超声速边界层感受性研究综述

实验流体力学 2017年第2期31卷 1-11页

作者：江贤洋李存标北京大学工学院湍流与复杂系统国家重点实验室北京100871 先进航空发动机协同创新中心北京100191

高超声速边界层感受性是边界层转捩预测与控制的关键环节,其对高超声速飞行器研究至关重要。目前关于高超声速边界层感受性的实验研究仍然十分匮乏,为了更好地理解高超声速边界层感受性过程并指导该领域的实验研究,文章梳理了近20年来... 详细信息

高超声速边界层感受性是边界层转捩预测与控制的关键环节,其对高超声速飞行器研究至关重要。目前关于高超声速边界层感受性的实验研究仍然十分匮乏,为了更好地理解高超声速边界层感受性过程并指导该领域的实验研究,文章梳理了近20年来国际上高超声速边界层感受性问题的研究内容,包括对自由流扰动和壁面扰动的感受性,并主要介绍了Fedorov的前缘感受性理论和模态转化机制。最后总结了自由流扰动中感受性的不同发展路径。

关键词：高超声速边界层感受性综述理论研究声波粗糙元壁面温度