论文标题
在侧向加热的立方体中，空气自然对流的分叉序列具有完美绝缘的水平和跨度边界
Sequence of bifurcations of natural convection of air in a laterally heated cube with perfectly insulated horizontal and spanwise boundaries
论文作者
论文摘要
研究了一个横向加热的立方体中浮力对流的三个稳定振荡过渡的序列，并研究了完全绝缘的水平和跨度边界。该问题由基于Krylov子空间迭代的牛顿和阿诺迪方法处理。有限体积网格逐渐从100^3到256^3有限体积。结果表明，主要的不稳定性的特征是两个竞争的本征模，它们的时间发育导致两个不同的振荡状态，它们的对称性有所不同。两种模式引起的分叉都是亚临界的。这些模式发展为不同的振荡和随机流状态，在较大的抓地力数下，稳定并到达单个稳定的稳定流量。随着Grashof数的进一步增加，该流量再次失去了稳定性。有人认为，由于不稳定的离心机制与热分层的稳定效果之间的相互作用，在所有三个过渡中，不稳定性以及稳定性的恢复。
A sequence of three steady - oscillatory transitions of buoyancy convection of air in a laterally heated cube with perfectly thermally insulated horizontal and spanwise boundaries is studied. The problem is treated by Newton and Arnoldi methods based on Krylov subspace iteration. The finite volume grid is gradually refined from 100^3 to 256^3 finite volumes. It is shown that the primary instability is characterized by two competing eigenmodes, whose temporal development results in two different oscillatory states that differ by their symmetries. Bifurcations due to both modes are subcritical. These modes develop into different oscillatory and then stochastic flow states, which, at larger Grashof number, stabilize and arrive to single stable steady flow. With further increase of the Grashof number this flow loses it stability again. It is argued that in all the three transitions, the instabilities onsets, as well as reinstatement of stability, take place owing to an interaction between a destabilizing centrifugal mechanism and stabilizing effect of thermal stratification.
