Plumes with non-monotonic mixing behaviour
Plumes with non-monotonic mixing behaviour
复制标题
具有非单调混合行为的羽流
DOI：
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发表时间：
1995
期刊：
影响因子：
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通讯作者：
A. Woods
中科院分区：
文献类型：
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作者：
Colm‐cille P. Caulfield;A. Woods
摘要：我们开发了一个模型的行为连续释放（羽流）的流体，在与环境流体混合，经历密度的非单调变化。这个模型可以模拟火山喷发云和热液羽流的行为。如果在源头，羽流最初实际上是负浮力射流，但有可能通过混合变成浮力，我们就确定了羽流坍塌的标准，并通过实验加以验证（见Woods和Caulfield， 1992）。在分层环境中，我们发现非线性混合羽流的最大高度总是低于常规的线性混合羽流，后者的初始浮力通量等于非线性混合羽流的潜在浮力通量。潜在浮力通量定义为羽流在离源较远的距离上通过混合所能发展的最大浮力通量，因为质量通量因夹带而变大。对于足够小的初始质量通量，…
Abstract We develop a model for the behaviour of continuous releases (plumes) of fluid which, upon mixing with the ambient fluid, undergo a non-monotonic change in density. This model serves as an analogue for the behaviour of volcanic eruption clouds and hydrothermal plumes. If, at the source, the plume is initially actually a negatively buoyant jet, but has the potential on mixing to become buoyant, we identify a criterion for collapse of the plume that is verified by experiment (see Woods and Caulfield, 1992). In a stratified environment, we show that a nonlinearly mixing plume always attains a lower maximum height than a conventional, Iinearly mixing plume whose initial buoyancy flux is equal to the potential buoyancy flux of the nonlinearly mixing plume. The potential buoyancy flux is defined as the maximum buoyancy flux that the plume fluid can develop through mixing at large distances from the source, as the mass flux becomes large due to entrainment. For sufficiently small initial mass fluxes, the...