论文标题
晶格玻尔兹曼方法的弯曲边界条件，用于模拟滑动流程中的微司酶流
Curved boundary conditions of the lattice Boltzmann method for simulating microgaseous flows in the slip flow regime
论文作者
论文摘要
晶格Boltzmann方法（LBM）显示出其在模拟微观气流中的有希望的能力。但是，合适的边界条件仍然是LBM建模涉及弯曲几何形状的小胶质酶流的关键问题之一。在本文中，提出了LBM的局部边界条件来处理小胶质酶流的弯曲固体壁。开发的边界处理结合了Maxwellian弥漫性反射方案和单节点边界方案，其中包含一个自由参数和距离比。在单向微流的多余时间（MRT）模型中分析了弯曲的边界条件。结果表明，派生的滑动速度取决于自由参数以及距离比和放松时间。根据自由参数，理论上确定了组合参数和均匀的松弛时间，以实现准确的滑移边界条件。此外，还发现，除了中途漫步反弹（DBB）方案外，先前的弯曲边界方案仅包含距离比不能确保均匀的松弛时间来实现滑移边界条件。进行了一些具有平面和弯曲边界的数值示例，以验证当前的弯曲边界方案。通过分析解决方案的数值预测的良好和稳健的一致性证明了我们的理论分析。
The lattice Boltzmann method (LBM) has shown its promising capability in simulating microscale gas flows. However, the suitable boundary condition is still one of the critical issues for the LBM to model microgaseous flows involving curved geometries. In this paper, a local boundary condition of the LBM is proposed to treat curved solid walls of microgaseous flows. The developed boundary treatment combines the Maxwellian diffuse reflection scheme and a single-node boundary scheme which contains a free parameter as well as the distance ratio. The curved boundary condition is analyzed within the multiple-relaxation-time (MRT) model for a unidirectional microflow. It is shown that the derived slip velocity depends on the free parameter as well as the distance ratio and relaxation times. By virtue of the free parameter, the combination parameter and the uniform relaxation time are theoretically determined to realize the accurate slip boundary condition. In addition, it is found that besides the halfway diffuse-bounce-back (DBB) scheme, previous curved boundary schemes only containing the distance ratio cannot ensure uniform relaxation times to realize the slip boundary condition. Some numerical examples with planar and curved boundaries are carried out to validate the present curved boundary scheme. The good and robust consistency of numerical predictions with analytical solutions demonstrates our theoretical analysis.
