Dynamical pressure for fluid mixtures with several temperatures

TL;DR

This paper introduces a new dynamical pressure term for fluid mixtures with components at different temperatures, relevant in non-equilibrium conditions and cosmological scenarios.

Contribution

It proposes a novel dynamical pressure associated with temperature differences in fluid mixtures, even without viscosity, expanding understanding of non-equilibrium fluid dynamics.

Findings

The dynamical pressure can be measured experimentally.

It is significant in cosmological evolution models.

Applicable to various physical situations involving temperature gradients.

Abstract

We consider binary mixtures of fluids with components having different temperatures. A new dynamical pressure term is associated with the difference of temperatures between components even if fluid viscosities are null. The non-equilibrium dynamical pressure can be measured and may be convenient in several physical situations as for example in cosmological circumstances where a dynamical pressure played a major role in the evolution of the early universe.