The energetics of flow through a rapidly oscillating tube. Part 1. General theory
The energetics of flow through a rapidly oscillating tube. Part 1. General theory
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DOI：
10.1017/s0022112009992904
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发表时间：
2010-04
影响因子：
3.7
通讯作者：
R. Whittaker;S. Waters;O. Jensen;J. Boyle;M. Heil
中科院分区：
文献类型：
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作者：
R. Whittaker;S. Waters;O. Jensen;J. Boyle;M. Heil
我们研究了任意横截面的柔性管的规定的壁驱动振荡的效果，通过该流动是由规定的下游端的稳定通量或两端之间的稳定压差驱动的。被认为是一个大Womersley数大Strouhal数制度，其中的振荡的壁是小的振幅，但足够快，以确保粘性效应被限制在一个薄的边界层。我们推导出渐近表达式的流场和评估的能量预算。提供了从流动到壁面的净能量传递为零的条件下的一般结果。这是作为一个关键的逆Strouhal数（无量纲的测量的背景流率），这是只表示在管的几何形状，流体性质和规定的壁振荡的轮廓。我们的研究结果确定了一个基本的自激振荡在三维可折叠管流的基本机制的一个重要组成部分，并使我们能够评估几何和流动特性如何影响系统的稳定性。
We examine the effect of prescribed wall-driven oscillations of a flexible tube of arbitrary cross-section, through which a flow is driven by prescribing either a steady flux at the downstream end or a steady pressure difference between the ends. A large-Womersley-number large-Strouhal-number regime is considered, in which the oscillations of the wall are small in amplitude, but sufficiently rapid to ensure viscous effects are confined to a thin boundary layer. We derive asymptotic expressions for the flow fields and evaluate the energy budget. A general result for the conditions under which there is zero net energy transfer from the flow to the wall is provided. This is presented as a critical inverse Strouhal number (a dimensionless measure of the background flow rate) which is expressed only in terms of the tube geometry, the fluid properties and the profile of the prescribed wall oscillations. Our results identify an essential component of a fundamental mechanism for self-excited oscillations in three-dimensional collapsible tube flows, and enable us to assess how geometric and flow properties affect the stability of the system.