Competing geometric and inertial effects on local flow structure in thick gravity-driven fluid films
Competing geometric and inertial effects on local flow structure in thick gravity-driven fluid films
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DOI：
10.1063/1.3041150
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发表时间：
2008-12
影响因子：
4.6
通讯作者：
M. Scholle;A. Haas;N. Aksel;M. Wilson;H. Thompson;P. Gaskell
中科院分区：
文献类型：
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作者：
M. Scholle;A. Haas;N. Aksel;M. Wilson;H. Thompson;P. Gaskell
考虑了波纹基板上厚重力驱动的自由表面膜流中涡流的形成和存在，用Stokes流的复变量方法半解析地求解了控制方程，当惯性显著时，通过完整的有限元公式对更一般的问题进行了数值求解。不同的几何形状（包括薄膜厚度或基材的振幅和波长的变化）和惯性的影响分别进行了探讨。对于斯托克斯流和不同的几何形状，在预测和现有的流动可视化以及与从附着流到局部分离流的转换相关的测量涡中心位置之间发现了非常好的一致性。本文认为，基于波纹长度尺度的局部雷诺数是衡量基底处惯性影响的适当方法。因为，对于小的局部雷诺数，那里的局部流动结构与i…
The formation and presence of eddies within thick gravity-driven free-surface film flow over a corrugated substrate are considered, with the governing equations solved semianalytically using a complex variable method for Stokes flow and numerically via a full finite element formulation for the more general problem when inertia is significant. The effect of varying geometry (involving changes in the film thickness or the amplitude and wavelength of the substrate) and inertia is explored separately. For Stokes-like flow and varying geometry, excellent agreement is found between prediction and existing flow visualizations and measured eddy center locations associated with the switch from attached to locally detached flow. It is argued that an appropriate measure of the influence of inertia at the substrate is in terms of a local Reynolds number based on the characteristic corrugation length scale. Since, for small local Reynolds numbers, the local flow structure there becomes effectively decoupled from the i...