【摘 要】
：
A theoretical model for identical coherent structures in the wall region of a turbulent boundary layer was proposed, using the idea of general resonant triad of
【机 构】
：
College of water Resources and Environment
论文部分内容阅读
A theoretical model for identical coherent structures in the wall region of a turbulent boundary layer was proposed, using the idea of general resonant triad of the hydrodynamic stability. The evolution of the structures in the wall region of a turbulent boundary layer was studied by combining the compact finite differences of high numerical accuracy and the Fourier spectral hybrid method for solving the three dimensional Navier-Stokes equations. In this method, the third order mixed explicit-implicit scheme was applied for the time integration. The fifth-order upwind compact finite difference schemes for the nonlinear convection terms in the physical space, and the sixth-order center compact schemes for the derivatives in spectral space were introduced, respectively. The fourth-order compact schemes satisfied by the velocities and pressure in spectral space was derived. As an application, the method was implemented to the wall region of a turbulent boundary to study the evolution of identical coherent structures. It is found that the numerical results are satisfactory.
其他文献
A two-phase approach is proposed to deal with the integration problem in the loop layout.Tabu search is applied to cell construction in phase 1 to minimize the
The paper introduced a special approach for diesel’s all-speed-govor modeling, which, in some cases,could solve the knotty problem frequently met in computer s
In rainy season, NaCl is adopted to trace sources of cave drip water, time scales of drip water responding to precipitation, and processes of water dynamics in
The present study is focused on the influence of a routine step, washing, following the preparation of calcined rare earth exchanged Y zeolite, on its hydrother
随着中国改革开放力度的不断加大和经济的快速健康发展，对外贸易和对外交流的活动也日趋平凡。商务谈判和交往是商务活动中的重要组成部分，然而其必然会受到中外文化的差异的影
The reaction kinetics of the oxidative dehydrogenation of propane was studied at 475-550℃over a VMgO catalyst. Vanadium-magnesium-oxides are among the most sel
用共沉淀法制备了SO4 2 -/ZrO2 -Al2 O3 固体超强酸 ,并采用低温陈化和添加稀土La对其制备方法进行改进 .通过样品催化正丁烷异构化反应考察了该固体超强酸中nZr和nAl的最佳
The microstructure changes of polypropylene induced by a complex combination of shearing, friction, compression and stretching actions during pan-milling were r
A new lupane-type triterpene was isolated from the resin of Boswellia carterii Birdw.Based on the Spectral methods,its structure was elucidated as lup-20(29)-en
Two alkaloids tylophoridicine D(1)and tylophoridicine E(2)have been isolated from tylophora atrofolliculata.The structures of the compounds were elucidated on t