arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2008.05213math.AP
收藏

导热流体退化扩散系统的存在性分析

Existence analysis of a degenerate diffusion system for heat-conducting fluids

Gianluca Favre, Ansgar Jüngel, Christian Schmeiser, Nicola Zamponi

AI总结:

本文研究含非等温碰撞算子的动理学方程在扩散极限下得到的导热流体交叉扩散模型,利用熵不等式、$H^{-1}$ 方法及重整化等技术证明其在密度或温度消失导致退化时仍存在全局弱解。

摘要:

本文证明了在有界区域中、满足无通量边界条件的一个抛物型能量输运系统存在全局弱解。该模型可在扩散极限下由一个含线性碰撞算子的动理学方程导出,其中碰撞算子涉及非等温 Maxwellian。局部温度的演化由一个热方程控制,其源项依赖于分布函数的能量。极限模型由具有熵结构的交叉扩散方程组成。主要困难在于非标准退化,即当流体密度或温度消失时,椭圆性会丧失。存在性证明基于由熵不等式和 $H^{-1}$ 方法得到的先验估计,以及数学流体动力学中的技术(重整化表述、div-curl 引理)。

英文摘要:

The existence of global weak solutions to a parabolic energy-transport system in a bounded domain with no-flux boundary conditions is proved. The model can be derived in the diffusion limit from a kinetic equation with a linear collision operator involving a non-isothermal Maxwellian. The evolution of the local temperature is governed by a heat equation with a source term that depends on the energy of the distribution function. The limiting model consists of cross-diffusion equations with an entropy structure. The main difficulty is the nonstandard degeneracy, i.e., ellipticity is lost when the fluid density or temperature vanishes. The existence proof is based on a priori estimates coming from the entropy inequality and the $H^{-1}$ method and on techniques from mathematical fluid dynamics (renormalized formulation, div-curl lemma).

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。

↑