李晓东
气动声学,计算气动声学,计算流体力学。
个性化签名
- 姓名:李晓东
- 目前身份:
- 担任导师情况:
- 学位:
-
学术头衔:
博士生导师, 教育部“新世纪优秀人才支持计划”入选者
- 职称:-
-
学科领域:
流动机械工程及流体动力工程
- 研究兴趣:气动声学,计算气动声学,计算流体力学。
李晓东,男,1967年出生,能源与动力工程学院教授。2007年被聘为北航蓝天学者特聘教授,美国航空航天协会通讯会士(Associate Fellow of AIAA), AIAA气动声学技术委员会国际委员,International Journal of Aeroacoustics国际期刊编委。
主要研究方向及特色:气动声学,计算气动声学,计算流体力学。
十余年来,李晓东教授先后主持了1项国家重点基础研究发展计划课题(973计划课题)、6项国家自然科学基金、2项博士点基金、1项武器装备预研基金、4项航空基础科学基金、1项航空支撑科技基金、3项国际合作及多项来自国内科研院所的课题。10多年来与德国、法国和美国多所大学的课题组在气动声学开展实质性合作交流与研究生交换。
获奖情况:1)2007 入选教育部“新世纪优秀人才”支持计划;2)2006 第八届中国航空学会青年科技奖;3)2002 获第八届霍英东基金会青年教师研究类三等奖;4)2002“特种功能蜂窝胶接结构制造技术”获国防科工委科技进步三等奖。
-
主页访问
2156
-
关注数
0
-
成果阅读
292
-
成果数
5
【期刊论文】Numerical simulation of the three-dimensional screech phenomenon from a circular jet
李晓东, X. D. Li a) and J. H. Gao b)
PHYSICS OF FLUIDS 20, 035101 (2008),-0001,():
-1年11月30日
Despite great advances on jet screech research during the past few decades, the prediction of jet screech amplitudes still remains a challenging task. The main objective of this paper is to develop an accurate three dimensional computational aeroacoustic procedure for the simulation of screech phenomenon from an underexpanded supersonic circular jet. The three dimensional Navier–Stokes equations and a modified two equation standard kturbulence model are solved in the generalized curvilinear coordinate system. A dispersion-relation preserving scheme is utilized for space discretization. The 2N storage low-dissipation and low-dispersion Runge–Kutta scheme is applied for time marching. Numerical results are presented and compared with available experimental data over Mach number range from 1.17 to 1.60. The predicted shock cell structure and radial density profiles agree very well with the measured results by Panda and Seasholtz ["Measurement of shock structure and shock vortex interaction in underexpanded jets using Rayleigh scattering," Phys. Fluids 11, 3761 (1999)]. In particular, it is shown that not only the predicted wavelengths, but also the amplitudes of the flapping and helical modes are in good agreement with experimental data by Ponton et al. ["Near field pressure fluctuations in the exit plane of a choked axisymmetric nozzle," NASA Tech. Memo TM-113137, 1997]. It is found that although the instantaneous flow fields accompanying the flapping and helical jet screech tones are not axisymmetric yet, the long time average mean flow field is still almost axisymmetric. This is because of the slow rotation of the flapping plane around the jet axis. The real time pressure signal of a Maj=1.30 screeching jet at r /D=2 in the nozzle exit plane is analyzed. The results indicate that the acoustic field of the simulated flapping and rotating motions of the screeching jet agree well with Ponton and Seiner's experimental measurements ["Acoustic study of B helical mode for choked axisymmetric nozzle," AIAA J. 33, 413 (1995)]. © 2008 American Institute of Physics. [DOI: 10.1063/1.2844474]
-
54浏览
-
0点赞
-
0收藏
-
0分享
-
169下载
-
0评论
-
引用
李晓东, Fang Q. Hu a, *, X.D. Li b, D.K. Lin b
Journal of Computational Physics 227(2008)4398-4424,-0001,():
-1年11月30日
Absorbing boundary conditions for the nonlinear Euler and Navier–Stokes equations in three space dimensions are presented based on the perfectly matched layer (PML) technique. The derivation of equations follows a three-step method recently developed for the PML of linearized Euler equations. To increase the efficiency of the PML, a pseudo mean flow is introduced in the formulation of absorption equations. The proposed PML equations will absorb exponentially the difference between the nonlinear fluctuation and the prescribed pseudo mean flow. With the nonlinearity in flux vectors, the proposed nonlinear absorbing equations are not formally perfectly matched to the governing equations as their linear counter parts are. However, numerical examples show satisfactory results. Furthermore, the nonlinearPMLreduces automatically to the linearPMLupon linearization about the pseudo mean flow. The validity and efficiency of proposed equations as absorbing boundary conditions for nonlinear Euler and Navier–Stokes equations are demonstrated by numerical examples. © 2008 Elsevier Inc. All rights reserved.
Non-reffecting boundary condition, Perfectly matched layer, Navier-Stokes equations, ulerequations, Computational fluid dynamics, Computational aeroacoustics
-
81浏览
-
0点赞
-
0收藏
-
0分享
-
651下载
-
0评论
-
引用
【期刊论文】Time-domain impedance boundary conditions for surfaces with subsonic mean flows
李晓东, X. D. Li a, C. Richter b) and F. Thiele c)
J. Acoust. Soc. Am., Vol.119, No.5, May 2006,-0001,():
-1年11月30日
The time-domain impedance boundary conditions of Tam and Auriault are extended for impedance boundaries with subsonic mean flows. This extension requires an effective impedance. A model for the effective impedance is proposed, which guarantees the continuity of particle displacement over an infinitely thin shear layer connecting the fluid to the impedance boundary as described by Myers. Together with the effective impedance model, the time domain impedance boundary condition renders the requirement of measuring the effective impedance under flow conditions unnecessary. To demonstrate the feasibility of the extended boundary conditions, a numerical validation using the NASA Grazing Incidence Tube measurements of Jones et al. is carried out. The assumed velocity on the infinitely thin shear layer connecting the flow over the surface to the locally reacting wall is shown to have a strong influence on the performance of the liner. Another important parameter identified is the shape of the mean flow profile, which not only causes convective effects but also may excite possible flow instabilities. It is demonstrated that satisfactory results can be obtained using the extended time domain impedance boundary condition based on the correct effective impedances and mean flow profiles. © 2006 Acoustical Society of America.
-
58浏览
-
0点赞
-
0收藏
-
0分享
-
342下载
-
0评论
-
引用
【期刊论文】Numerical simulation of the generation mechanism of axisymmetric supersonic jet screech tones
李晓东, X. D. Li a) and J. H. Gao b)
PHYSICS OF FLUIDS 17, 085105 (2005),-0001,():
-1年11月30日
In this paper an axisymmetric computational aeroacoustic procedure is developed to investigate the generation mechanism of axisymmetric supersonic jet screech tones. The axisymmetric Navier-Stokes equations and the two equations standard k-e turbulence model modified by Turpin and Troyes ["Validation of a two-equation turbulence model for axisymmetric reacting and non-reaction flows," AIAA Paper No. 2000-3463 (2000)] are solved in the generalized curvilinear coordinate system. A generalized wall function is applied in the nozzle exit wall region. The dispersion-relation-preserving scheme is applied for space discretization. The 2N storage low-dissipation and low dispersion Runge-Kutta scheme is employed for time integration. Much attention is paid to far-field boundary conditions and turbulence model. The underexpanded axisymmetric supersonic jet screech tones are simulated over the Mach number from 1.05 to 1.2. Numerical results are presented and compared with the experimental data by other researchers. The simulated wavelengths of A0, A1, A2, and B modes and part of simulated amplitudes agree very well with the measurement data by Ponton and Seiner ["The effects of nozzle exit lip thickness on plume resonance," J. Sound Vib. 154, 531 (1992)]. In particular, the phenomena of modes jumping have been captured correctly although the numerical procedure has to be improved to predict the amplitudes of supersonic jet screech tones more accurately. Furthermore, the phenomena of shock motions are analyzed. The predicted splitting and combination of shock cells are similar with the experimental observations of Panda ["Shock oscillation in underexpanded screeching jets," J. Fluid. Mech. 363, 173 (1998)]. Finally, the receptivity process is numerically studied and analyzed. It is shown that the receptivity zone is associated with the initial thin shear layer, and the incoming and reflected sound waves. © 2005 American Institute of Physics. [DOI: 10.1063/1.2033909]
-
34浏览
-
0点赞
-
0收藏
-
0分享
-
124下载
-
0评论
-
引用
【期刊论文】AN INVERSE AEROACOUSTIC PROBLEM ON ROTOR WAKE/STATOR INTERACTION
李晓东, J. LUO AND X. D. LI
Journal of Sound and Vibration (2002) 254 (2), 219-229,-0001,():
-1年11月30日
An inverse aeroacoustic model on rotor wake/stator interaction is proposed based on the linearized Euler equations. The sound "eld is related to the pressure distribution on the stator surface in the formof a Fredholm integral equation of the "rst kind which is a well-known ill-posed problem. Since the sound "eld is fully speci"ed, numerical inversion allows the reconstruction of the pressure distribution on the stator surface. For solving the discrete ill-posed problem, the singular-value decomposition technique coupled with the Tikhonov regularization method is applied to stabilize the solution. The optimal regularization parameter is chosen by the generalized cross-validation criterion and the discrete Picard condition is employed to analyze the ill-posedness of the inverse problem. Numerical results show that the reconstruction is fairly good when the signal-to-noise ratio is not very low. The results become inaccurate when the noise dominates over the observer signal. In addition, numerical results also indicate the importance of the reduced frequency. The higher the reduced frequency, the better the reconstruction results.
-
65浏览
-
0点赞
-
0收藏
-
0分享
-
222下载
-
0评论
-
引用