TURBULENT BUOYANT CONVECTION FROM A SOURCE IN A CONFINED REGION
TURBULENT BUOYANT CONVECTION FROM A SOURCE IN A CONFINED REGION
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DOI：
10.1017/s0022112069000413
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发表时间：
1969-01-01
影响因子：
3.7
通讯作者：
TURNER, JS
中科院分区：
文献类型：
--
作者：
BAINES, WD;TURNER, JS
本文考虑了当感兴趣区域有界时，小浮力源的连续对流对环境特性的影响。主要假设是，进入湍流浮力区域的夹带速率与当地平均向上速度成正比，并且浮力元素在该区域的顶部展开，并成为该水平处非湍流环境的一部分。对于来自点源和线源的羽流以及周期性释放的热气流的情况，获得了在长时间内有效的渐近解。这些都具有环境稳定分层的特性，密度剖面形状固定，在各个层面上以统一的时间速率变化，并且处处下降（浮力元素上升）。对恒定横截面环境中的点源进行了详细分析。对此案例进行了实验室实验，验证了该理论的主要预测。然后展示了如何扩展该方法以包括更现实的对流起始条件以及有界环境的一般形状。最后，将该模型定量地应用于工程、大气和海洋中的各种问题，并讨论了其使用的局限性。
This paper considers the effect of continuous convection from small sources of buoyancy on the properties of the environment when the region of interest is bounded. The main assumptions are that the entrainment into the turbulent buoyant region is at a rate proportional to the local mean upward velocity, and that the buoyant elements spread out at the top of the region and become part of the non-turbulent environment at that level. Asymptotic solutions, valid at large times, are obtained for the cases of plumes from point and line sources and also periodically released thermals. These all have the properties that the environment is stably stratified, with the density profile fixed in shape, changing at a uniform rate in time at all levels, and everywhere descending (with ascending buoyant elements).The analysis is carried out in detail for the point source in an environment of constant cross-section. Laboratory experiments have been conducted for this case, and these verify the major predictions of the theory. It is then shown how the method can be extended to include more realistic starting conditions for the convection, and a general shape of bounded environment. Finally, the model is applied quantitatively to a variety of problems in engineering, the atmosphere and the ocean, and the limitations on its use are discussed.