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The hydrothermal wave of large-Prandtl-number fluid in a shallow cavity

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Science China(Physics,Mechanics & Astronomy) 2007年第6期50卷 787-796页

作者： tang zemei HU WenRui National Microgravity Laboratory Institute of MechanicsChinese Academy of SciencesBeijing 100080China

The hydrothermal wave was investigated numerically for large-Prandtl-number fluid (Pr = 105.6) in a shallow cavity with different heated sidewalls. The traveling wave appears and propagates in the direction opposite to the surface flow (upstream) in the case of zero gravity when the applied temperature difference grows and over the critical value. The phase relationships of the disturbed velocity,temperature and pressure demonstrate that the traveling wave is driven by the disturbed tem-perature,which is named hydrothermal wave. The hydrothermal wave is so weak that the oscillatory flow field and temperature distribution can hardly be observed in the liquid layer. The exciting mechanism of hydrothermal wave is analyzed and discussed in the present paper.

关键词： hydrothermal wave numerical simulation microgravity

Influence of the heating rate on the critical Marangoni number of oscillatory thermocapillary convection in the floating half zone

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Science China(Physics,Mechanics & Astronomy) 2012年第1期55卷 102-107页

作者： LI Kai tang zemei HU WenRui National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

In the present study, numerical simulations were conducted on thermocapillary convection in floating half zones of 5 cSt silicone oil of different scales in comparison with the experimental studies in the microgravity conditions. The effect of heating rate on the marginal instability boundaries is indicated as a possible explanation for the significant quantitative discrepancies between the experimental results in the terrestrial conditions and in the microgravity conditions.

关键词： thermocapillary convection flow instability finite element methods

Period-doubling bifurcations of the thermocapillary convection in a floating half zone

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Science China(Physics,Mechanics & Astronomy) 2010年第9期53卷 1681-1686页

作者： AA Yan,LI Kai,tang zemei,CAO ZhongHua & HU WenRui National Microgravity Laboratory,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China Chinese Academy of Sciences National Microgravity Laboratory Institute of Mechanics Beijing China (GRID:grid.9227.e) (ISNI:***)

This study experimentally explored the fine structures of the successive period-doubling bifurcations of the time-dependent thermocapillary convection in a floating half zone of 10 cSt silicone oil with the diameter d0=3.00 mm and the aspect ratio A=l/d0=0.72 in terrestrial *** onset of time-dependent thermocapillary convection predominated in this experimental configuration and its subsequent evolution were experimentally detected through the local temperature *** experimental results revealed a sequence of period-doubling bifurcations of the time-dependent thermocapillary convection,similar in some way to one of the routes to chaos for buoyant natural *** critical frequencies and the corresponding fractal frequencies were extracted through the real-time analysis of the frequency spectra by Fast-Fourier-Transfor-mation(FFT).The projections of the trajectory onto the reconstructed phase-space were also ***,the experimentally predicted Feigenbaum constants were quite close to the theoretical asymptotic value of 4.669 [Feigenbaum M *** Lett A,1979,74:375-378].

关键词： thermocapillary convection bifurcation transition to turbulence

Numerical study on onset of oscillatory thermocapillary flow in rectangular liquid pool

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Science China(Technological Sciences) 2010年第4期53卷 1069-1076页

作者： HU WenRui,tang zemei & LI Kai Key Laboratory of Microgravity(National Microgravity Laboratory),Institute of Mechanics,Chinese Academy of Sciences,Beijing10090,China Key Laboratory of Microgravity (National Microgravity Laboratory) Institute of Mechanics Chinese Academy of Sciences

Thermocapillary flow in a rectangular liquid pool of large Prandtl fluid(Pr=105.6) is numerically studied in *** thermocapillary flow arises when the imposed temperature difference between the sidewalls exceeds a critical *** fluctuations of the oscillatory flow,accompanied by the propagation of the hydrothermal wave from the cold sidewall to the hot one,are much smaller than the time-averaged velocity and temperature *** corresponding disturbance cells arise in the centre of the liquid pool initially,and extend to the whole region with the increasing imposed temperature *** present study reveals the different characteristics of the oscillatory themocapillary flow in the rectangular liquid pool as compared to the cases in other configurations.

关键词： hydrothermal wave bifurcation numerical simulation microgravity

THE PISTON MODEL FOR CORONAL TRANSIENT WITH FORERUNNER

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Science in China,Ser.A 1986年第7期 755-763页

作者：唐泽眉胡文瑞 Institute of Mechanics Academia Sinica Beijing

The observational data show that large scale loop or bubble-like coronal transients frequently associate with forerunners. The forerunner should be related to the rapid motion of the transient behind it, and they are controlled by the same dynamic process. In the present paper, the gasdynamic model with a spherical piston moving at certain speed in the solar gravitational field is devoted to studying the coronal transient with a forerunner. In comparison with observations, the theoretical results show that the piston model may, reasonably explain the configuration, kinetic and dynamic features in the regions of both forerunner and high-speed transient behind it.

关键词： THE PISTON MODEL FOR CORONAL TRANSIENT WITH FORERUNNER

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半浮区液桥热毛细振荡流

力学学报 1999年第4期31卷 415-422页

作者：唐泽眉阿燕胡文瑞中国科学院力学研究所北京100080

采用非定常、三维直接数值模拟方法研究大Pr数半浮区液桥热毛细对流从定常流向振荡流的过渡过程．文中详细描述了热毛细振荡流的起振和振荡特征，给出了液桥横截面上振荡流的流场和温度分布．在地面引力场条件下计算的结果与地面实验的... 详细信息

采用非定常、三维直接数值模拟方法研究大Pr数半浮区液桥热毛细对流从定常流向振荡流的过渡过程．文中详细描述了热毛细振荡流的起振和振荡特征，给出了液桥横截面上振荡流的流场和温度分布．在地面引力场条件下计算的结果与地面实验的结果进行比较，得出液桥水平截面上的流场和温度分布图样以一定的速度旋转，自由表面固定点处流体的环向流速正、负交替变化的一致结论．

关键词：热毛细对流微重力流体力学半浮区液桥

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磁场的对流再产生和扩散

Chinese Journal of Astronomy and Astrophysics 1988年第2期 117-123页

作者：唐泽眉中国科学院力学研究所

根据双尺度平均场电动力学,研究一种特定的周期对流的磁场再产生和扩散效应。数值计算运动学发电机方程,给出旋转对流元中感应电动势图象,得出无量纲磁场再产生系数α′≈-0.4～+0.4;对流扩散系数β′≈0.05.所提供的α效应能满足符合... 详细信息

根据双尺度平均场电动力学,研究一种特定的周期对流的磁场再产生和扩散效应。数值计算运动学发电机方程,给出旋转对流元中感应电动势图象,得出无量纲磁场再产生系数α′≈-0.4～+0.4;对流扩散系数β′≈0.05.所提供的α效应能满足符合太阳活动周期的α-ω发电机模型的要求,若取对流元特征旋转速度u1为100m/s,对流元特征长度α为1000km计算得到的对流扩散效应较发电机理论和观测的要求约小20倍。需计入脉动磁场和平均流场的相互作用,进一步研究旋转对流元的扩散效应。

关键词：磁流力学周期对流太阳磁场

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强引力场中活塞运动的球对称解

力学学报 1985年第6期 499-506页

作者：唐泽眉中国科学院力学研究所

本文研究在强引力场中活塞的球对称匀速运动问题,对三种不同强度的引力场,用特征线法数值求解流体力学方程组,得出符合激波间断条件及稀疏波边界条件的解。文中详细地描述了活塞的运动图象、激波传播速度、活塞面上声速分布以及活塞扰... 详细信息

本文研究在强引力场中活塞的球对称匀速运动问题,对三种不同强度的引力场,用特征线法数值求解流体力学方程组,得出符合激波间断条件及稀疏波边界条件的解。文中详细地描述了活塞的运动图象、激波传播速度、活塞面上声速分布以及活塞扰动区流场,分析讨论了引力场对球对称活塞运动的影响。

关键词：活塞运动引力作用唐泽图象引力场激波传播压缩区稀疏区球对称解

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具有核球和盘的盘状星系三维质量分布

Chinese Journal of Astronomy and Astrophysics 1984年第1期 43-48页

作者：唐泽眉中国科学院力学研究所

观测指出,盘状星系有两个主要组成部分,中心椭球和外盘.在早型的以发光天体为主体的盘状星系中,根据光度分布规律可以得到面密度分布.本文根据中心具有核球的盘状星系面密度分布曲线和旋转曲线,用数值方法求解流体力学方程组和泊松方程... 详细信息

观测指出,盘状星系有两个主要组成部分,中心椭球和外盘.在早型的以发光天体为主体的盘状星系中,根据光度分布规律可以得到面密度分布.本文根据中心具有核球的盘状星系面密度分布曲线和旋转曲线,用数值方法求解流体力学方程组和泊松方程,得出盘状星系中心区域的三维质量分布和弥散速度分布.结果表明,盘状星系的中心椭球为一高密度区,此区中的恒星或星团与椭圆星系的成员具有近似的动力学特征.这些结果与观测是一致的.

关键词：星系盘状核球椭球密度分布质量分布