Turbulent Boundary Layer at Large Re
Turbulent Boundary Layer at Large Re
复制标题
大范围湍流边界层 Re
DOI：
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发表时间：
2016
期刊：
影响因子：
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通讯作者：
V. Cardoş
中科院分区：
文献类型：
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作者：
H. Dumitrescu;V. Cardoş
流体作为一种没有自身形状的可变形体，从静止开始时，会经历流动的流体与标志流动边界的物理表面之间的相互作用。这些相互作用是一种碰撞过程，其中两个碰撞体（即流动及其边界面）之间存在动量交换。在短时间内的接触后的冲击剪切流发生两个主要的影响是由流动引起的碰撞触发了：戏剧性的动量和边界涡量的重新分配，其次是剪切应力/粘度的变化，在微观结构的流体，在开始表现为线性反应介质和非线性色散介质。起动流的扰动引起壁面有界流的纠缠，形成点涡或集中涡球，从而产生波并在流场中传播。本文发展了一种波机制的集中边界涡的运输，直接关系到迷人的湍流现象，使用的涡丝的扭转概念与假设的触变性/非线性粘性流体。
The fluids as deformable bodies without own shape, when starting from rest, experience interactions between the flowing fluid and the physical surfaces marking the bounds of flow. These interactions are a kind of impact process where there is a momentum exchange between two colliding bodies, i.e. the flow and its boundary surfaces. Within a short time of contact a post-impact shear flow occurs where two main effects are triggered off by the flow-induced collision: dramatic redistribution of the momentum and the boundary vorticity followed by the shear stress/viscosity change in the microstructure of the fluid which at the beginning behaves as linear reactive medium and latter as nonlinear dispersive medium. The disturbance of the starting flow induces the entanglement of the wall-bounded flow in the form of point-vortices or concentrated vorticity balls whence waves are emitted and propagated through flow field. The paper develops a wave mechanism for the transport of the concentrated boundary vorticity, directly related to the fascinating turbulence phenomenon, using the torsion concept of vorticity filaments associated with the hypothesis of thixotropic/nonlinear viscous fluid.