Nonlinear Stresses and Temperatures in Transient Adiabatic and Shear Flows via Nonequilibrium Molecular Dynamics -- Three Definitions of Temperature

TL;DR

This paper compares different definitions of temperature and stress in adiabatic shear flows using large-scale nonequilibrium molecular dynamics simulations, revealing insights into local temperature measures and rotational effects.

Contribution

It introduces an improved form for local stream velocity and highlights rotational contributions to configurational temperature in shear flows.

Findings

Kinetic temperature tensors differ from configurational temperatures.

Rotational effects significantly influence configurational temperature.

Enhanced local velocity estimation improves flow analysis.

Abstract

We compare nonlinear stresses and temperatures for adiabatic shear flows, using up to 262,144 particles, with those from corresponding homogeneous and inhomogeneous flows. Two varieties of kinetic temperature tensors are compared to the configurational temperatures. This comparison leads to an improved form for the local and instantaneous smooth-particle averaged stream velocity and to a recognition of rotational contributions to the configurational temperature.