Vertically distributed wall sources of buoyancy. Part 1. Unconfined
Vertically distributed wall sources of buoyancy. Part 1. Unconfined
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垂直分布的壁浮力源。
DOI：
10.1017/jfm.2020.808
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发表时间：
2020
影响因子：
3.7
通讯作者：
Parker D
中科院分区：
文献类型：
--
作者：
Parker D
我们研究了一个紊流分布壁源羽流：由均匀的垂直壁面浮力源产生的流动，例如由均匀加热或冷却的垂直壁面产生的流动。垂直分布的浮力源是通过强迫密集的盐水溶液通过多孔壁而产生的。首先在垂直于壁面的垂直平面上进行速度测量，检查壁面的全高度，以确定大块流动已经完全湍流，自相似并在体积，动量和浮力之间达到不变平衡的区域。同时给出了该区域的速度和浮力场测量结果，并确定了夹带系数。与浮力驱动的无界流动（如自由线羽流）相比，这个值很小，我们认为这是由于刚性边界的存在限制了蜿蜒和湍流的产生，而不是垂直分布的浮力源的影响。给出了湍流速度和浮力统计数据，为了获得对流动行为的物理见解，将结果与其他典型浮力驱动的自由流动和壁面有界流动的结果进行了比较。我们表明，通过考虑特征垂直速度和恒定的夹带系数，可以捕获分布壁源羽流的大量混合。这种混合被刚性边界的存在和特征速度的降低（与壁线羽流相比）所抑制。
We examine a turbulent distributed wall-source plume: the flow resulting from a uniform vertical wall source of buoyancy such as that produced by an evenly heated or cooled vertical wall. The vertically distributed buoyancy source is created by forcing dense salt water solution through a porous wall. Velocity measurements on a vertical plane normal to the wall are first presented examining the full height of the wall in order to identify the region in which the bulk flow has become fully turbulent, self-similar and reached an invariant balance between the fluxes of volume, momentum and buoyancy. Simultaneous velocity and buoyancy field measurements are then presented in this region and an entrainment coefficient of is determined. This value is small compared to that of buoyancy-driven unbounded flows, e.g. a free line plume, and we reason this to be due to the presence of a rigid boundary restricting meandering and turbulence production, rather than the effect of the vertically distributed source of buoyancy. Turbulent velocity and buoyancy statistics are presented and, in order to gain physical insights into the flow behaviour, the results are compared to those of other canonical buoyancy-driven free and wall-bounded flows. We show that the bulk mixing of distributed wall-source plumes can be captured by consideration of the characteristic vertical velocities and a constant entrainment coefficient. This mixing is inhibited both by the presence of a rigid boundary and the reduced characteristic velocities (compared to those of wall line plumes).
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影响因子：
3.7
作者：
M. Hölling;H. Herwig
通讯作者：
H. Herwig
影响因子：
3.7
作者：
C. McConnochie;R. C. Kerr
通讯作者：
R. C. Kerr
寒冷垂直表面的气流风险
影响因子：
7.4
作者：
P. Heiselberg
通讯作者：
P. Heiselberg
DOI：
--
发表时间：
1993
期刊：
影响因子：
--
作者：
A. Ferrier;D. R. Funk;P. Roberts
通讯作者：
P. Roberts
影响因子：
--
作者：
G. Vliet;C. K. Liu
通讯作者：
G. Vliet;C. K. Liu