Numerical prediction of natural convection in a tall enclosure
Numerical prediction of natural convection in a tall enclosure
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高围护结构中自然对流的数值预测
DOI：
10.1002/fld.390
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
D. Christopher
中科院分区：
文献类型：
--
作者：
D. Christopher
对高腔内自然对流流动方程求解了一个超临界瑞利数，在这个临界瑞利数下，流场发生振荡，有多种可能的解。目的是比较这种复杂流动情况下的各种解决方法。采用各种时间积分方法、时间步长和网格间距，采用加权残差法的伽辽金形式进行有限元求解。欧拉时间积分法因其耗散过大而不适用于该问题。要准确预测腔内的平均温度和速度，需要精细的网格分布和小的时间步长，而要准确预测振荡的幅度，则需要更精细的元素和时间步长。初始均匀的温度分布导致均匀振荡的斜对称流场。温度场由初始的随机温度场演变为打破对称的流场，经过很长时间后，最终达到歪斜对称的流场。版权所有©2002约翰威利父子有限公司
The equations for natural convection flow in a tall cavity were solved for a super‐critical Rayleigh number for which oscillations occur in the flow field and various solutions are possible. The objective was to compare various solution methods for this complex flow situation. The equations were solved using the finite element method with the Galerkin form of the method of weighted residuals with various time integration methods, time steps and grid spacings. The Euler time integration method is unsuitable for this problem because of its excessive dissipation. Fine grid distributions and small time steps were needed to predict accurate values of the average temperatures and velocities in the cavity, with even finer elements and time steps needed to accurately predict the amplitudes of the oscillations. An initially uniform temperature distribution lead to a uniformly oscillating skew‐symmetric flow field. An initially random temperature field lead to a symmetry‐breaking flow field that eventually reached the skew‐symmetric flow field after a long time. Copyright © 2002 John Wiley & Sons, Ltd.