两种不同结构的混合流体局部行波对流斑图

发布时间：2018-05-18 15:10

本文选题：混合流体 + 局部行波　；参考：《科学通报》2016年08期

【摘要】：通过流体力学基本方程组的二维数值模拟,探讨了长高比?=20的矩形腔体中有较强Soret效应的混合流体对流中的局部行波的形成及含有缺陷的局部行波的动力学特性.当分离比?=?0.60时,在分叉曲线的鞍结分叉点附近相对Rayleigh数为r=1.926~2.074的范围内,出现了无缺陷局部行波.然后,随r逐渐增加,系统由无缺陷局部行波过渡到含有缺陷的局部行波并在r=2.075~2.224的范围内形成稳定的含有缺陷的局部行波.局部行波对流的宽度随r增加而增加,并在r=2.075处随着对流斑图的转变突然加宽.再随r增加,含有缺陷的局部行波失去稳定,对流控制整个腔体并演化成有缺陷的行波.有缺陷的局部行波是我们发现的新型对流结构.有缺陷的局部行波的形成依赖于局部行波的对流宽度.在具有缺陷的局部行波存在范围内,这种缺陷出现的周期随r增大而增加.
[Abstract]:Based on the two-dimensional numerical simulation of the basic equations of hydrodynamics, the formation of local traveling waves in convection of mixed fluid with strong Soret effect and the dynamic characteristics of local traveling waves with defects in rectangular cavity with a ratio of length to height of 20 are discussed. When the separation ratio is 0.60, within the range of relative Rayleigh number of 1.9262.074 near the saddle node bifurcation point of the bifurcation curve, a non-defect local traveling wave appears. Then, with the increase of r, the system transition from non-defect local traveling wave to local defect traveling wave and forming a stable local traveling wave with defect in the range of rn 2.075 / 2.224. The width of local traveling wave convection increases with the increase of r, and suddenly widens with the transition of convection pattern at r 2. 075. With the increase of r, the local traveling wave with defects becomes unstable, and the convection controls the whole cavity and evolves into a defective traveling wave. The defective local traveling wave is a new type of convection structure found by us. The formation of defective local traveling waves depends on the convection width of the local traveling waves. In the range of local traveling waves with defects, the period of occurrence of these defects increases with the increase of r.
【作者单位】：西安理工大学西北旱区生态水利工程国家重点实验室培育基地;中水珠江规划勘测设计有限公司;
【基金】：国家自然科学基金(10872164) 陕西省重点学科建设专项资金(00X901)资助
【分类号】：O35

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