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arXiv 1502.01206math.APmath-phmath.MPnlin.SIphysics.flu-dyn
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三维非定常不可压Navier-斯托克斯方程通解的存在性

On existence of general solution of the Navier-Stokes equations for 3D non-stationary incompressible flow

Sergey V. Ershkov

摘要:

本文考虑了Navier-斯托克斯方程通解的一种新表示。我们考虑三维非定常不可压缩流的运动方程。流速场和动量方程应分解为两个分量之和:无旋(无旋)分量和螺线管(无发散)分量。动量方程中明显无旋(无旋)的部分用于获得压力梯度分量。作为这样一个方程的一项,我们使用了无旋(无旋)的流速向量场,这是由适当的潜力(此外,连续性方程确定这样一个潜在的调和函数)。动量方程的另一部分也可以分解为两个方程之和:-对于流速场(无粘性),旋度为零,以及适当的方程。具有粘性效应但卷曲可变。螺线管方程具有粘性效应的流动由具有可变旋度的流速的每个分量的固有热方程表示。非粘性情况由3个线性微分方程(关于时间参数)的偏微分方程系统表示,取决于上述热方程的解的分量。对于具有可变旋度的流速分量。因此,Navier-斯托克斯方程通解的存在性问题被证明为这样的PDE-线性方程组的真解的存在性问题。最终的解决方案被证明是2个组件的总和:-无旋(无旋)和螺线管(可变旋度)组件。

英文摘要:

A new presentation of general solution of Navier-Stokes equations is considered here. We consider equations of motion for 3-dimensional non-stationary incompressible flow. The field of flow velocity as well as the equation of momentum should be split to the sum of two components: an irrotational (curl-free) one, and a solenoidal (divergence-free) one. The obviously irrotational (curl-free) part of equation of momentum used for obtaining of the components of pressure gradient. As a term of such an equation, we used the irrotational (curl-free) vector field of flow velocity, which is given by the proper potential (besides, the continuity equation determines such a potential as a harmonic function). The other part of equation of momentum could also be split to the sum of 2 equations: - with zero curl for the field of flow velocity (viscous-free), and the proper Eq. with viscous effects but variable curl. A solenoidal Eq. with viscous effects is represented by the proper Heat equation for each component of flow velocity with variable curl. Non-viscous case is presented by the PDE-system of 3 linear differential equations (in regard to the time-parameter), depending on the components of solution of the above Heat Eq. for the components of flow velocity with variable curl. So, the existence of the general solution of Navier-Stokes equations is proved to be the question of existence of the proper solution for such a PDE-system of linear equations. Final solution is proved to be the sum of 2 components: - an irrotational (curl-free) one and a solenoidal (variable curl) components.

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。

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