arXivDaily arXiv每日学术速递 周一至周五更新
arXiv math/0408032math.AP
收藏

一类涡量播种模型弱解的存在唯一性

On the existence and uniqueness of weak solutions for a vorticity seeding model

L. C. Berselli, M. Romito

摘要:

在本文中,我们研究了Navier-斯托克斯方程与Navier型边界条件,已被提出作为一种替代常见的近壁模型。我们研究的边界条件,涉及速度的切向部分和柯西应力矢量的切向部分之间的线性关系,与湍流计算方法中引入的涡量播种模型有关。在边界层区域,逐点非零法向通量的存在可以被认为是避免使用现象学近壁模型的一种工具。最后,结合大涡模拟研究的最新进展,对问题进行了分析。在二维情况下,我们证明了弱解的存在性和唯一性,通过使用相当基本的工具,希望也可以理解的应用人工作的湍流。的解的渐近行为,相对于平均半径$δ,$也进行了研究。特别是,我们证明了收敛的解决方案对相应的解决方案的斯托克斯方程与通常的无滑移边界条件,作为小参数$δ$趋于零。

英文摘要:

In this paper we study the Navier-Stokes equations with a Navier-type boundary condition that has been proposed as an alternative to common near wall models. The boundary condition we study, involving a linear relation between the tangential part of the velocity and the tangential part of the Cauchy stress-vector, is related to the vorticity seeding model introduced in the computational approach to turbulent flows. The presence of a point-wise non vanishing normal flux may be considered as a tool to avoid the use of phenomenological near wall models, in the boundary layer region. Furthermore, the analysis of the problem is suggested by recent advances in the study of Large Eddy Simulation. In the two dimensional case we prove existence and uniqueness of weak solutions, by using rather elementary tools, hopefully understandable also by applied people working on turbulent flows. The asymptotic behaviour of the solution, with respect to the averaging radius $δ,$ is also studied. In particular, we prove convergence of the solutions toward the corresponding solutions of the Navier-Stokes equations with the usual no-slip boundary conditions, as the small parameter $δ$ goes to zero.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑