Blast in a One-Dimensional Cold Gas: From Newtonian Dynamics to Hydrodynamics
Blast in a One-Dimensional Cold Gas: From Newtonian Dynamics to Hydrodynamics
复制标题
DOI：
10.1103/physrevlett.126.244503
复制
发表时间：
2021-06-16
影响因子：
8.6
通讯作者：
Dhar, Abhishek
中科院分区：
文献类型：
--
作者：
Chakraborti, Subhadip;Ganapa, Santhosh;Dhar, Abhishek
由大量原子组成的气体根据牛顿动力学演化，通常用连续流体力学来描述。严格证明这是一个突出的开放问题，和精确的数值演示的等效性的流体动力学和微观的描述是罕见的。我们测试这种等价性的背景下，爆炸波的演变，一个问题，预计将在流体力学可以工作的极限。我们研究了一个一维静止气体与瞬时局部释放的能量，流体动力学欧拉方程承认一个自相似的标度解。我们的微观模型由硬点粒子与交替质量，这是一个不可积系统与强混合动力学。我们广泛的微观模拟发现一个显着的协议与欧拉流体力学，偏差在一个小的核心区域，被理解为由于热传导而产生的。
A gas composed of a large number of atoms evolving according to Newtonian dynamics is often described by continuum hydrodynamics. Proving this rigorously is an outstanding open problem, and precise numerical demonstrations of the equivalence of the hydrodynamic and microscopic descriptions are rare. We test this equivalence in the context of the evolution of a blast wave, a problem that is expected to be at the limit where hydrodynamics could work. We study a one-dimensional gas at rest with instantaneous localized release of energy for which the hydrodynamic Euler equations admit a self-similar scaling solution. Our microscopic model consists of hard point particles with alternating masses, which is a nonintegrable system with strong mixing dynamics. Our extensive microscopic simulations find a remarkable agreement with Euler hydrodynamics, with deviations in a small core region that are understood as arising due to heat conduction.