论文标题
使用中镜晶格玻尔兹曼算法的不混溶瑞利 - 泰勒湍流
Immiscible Rayleigh-Taylor turbulence using mesoscopic lattice Boltzmann algorithms
论文作者
论文摘要
我们研究了由雷利 - 泰勒（RT）不稳定性诱导的湍流，该湍流是通过使用在GPU上实现的Shan-chen pseudoptential实现的多组分晶格玻尔兹曼方法的2D不混溶两组分流的。我们将我们的结果与Chertkov和合作者研究的不混溶3D RT的现象学理论的2D案例进行了比较（{\ IT物理评论E 71，055301，2005}）。此外，我们比较了混合层的生长，典型的速度，平均密度曲线和肠胃植物与等效的情况，但对于可混杂的两个组分流体。无论是在可混杂的情况和不混溶的情况下，混合层的预期二次生长和典型速度的线性生长都可以使用长期长期渐近预成分，但初始瞬态却不同。在不混溶的情况下，endstrophy显示出一种像$ \ propto t^{3/2} $一样生长的趋势，涡度的最高值集中在接近界面附近。此外，我们研究了典型的液滴大小的演变以及类似乳液状态下界面总长度的行为，显示了与我们的现象学预测兼容的幂律行为的存在。我们的结果也可以被视为扩展晶格Boltzmann工具应用3D不混溶案例的第一个验证步骤。
We studied turbulence induced by the Rayleigh-Taylor (RT) instability for 2D immiscible two-component flows by using a multicomponent lattice Boltzmann method with a Shan-Chen pseudopotential implemented on GPUs. We compare our results with the extension to the 2D case of the phenomenological theory for immiscible 3D RT studied by Chertkov and collaborators ({\it Physical Review E 71, 055301, 2005}). Furthermore, we compared the growth of the mixing layer, typical velocity, average density profiles and enstrophy with the equivalent case but for miscible two-component fluid. Both in the miscible and immiscible cases, the expected quadratic growth of the mixing layer and the linear growth of the typical velocity are observed with close long-time asymptotic prefactors but different initial transients. In the immiscible case, the enstrophy shows a tendency to grow like $\propto t^{3/2}$, with the highest values of vorticity concentrated close to the interface. In addition, we investigate the evolution of the typical drop size and the behavior of the total length of the interface in the emulsion-like state, showing the existence of a power law behavior compatible with our phenomenological predictions. Our results can also be considered as a first validation step to extend the application of lattice Boltzmann tool to study the 3D immiscible case.
