Kinetic Simulations of Compressible Non-Ideal Fluids: From Supercritical Flows to Phase-Change and Exotic Behavior

TL;DR

This paper introduces a kinetic model for compressible non-ideal fluids that accurately simulates complex phenomena like phase change, supercritical flows, and shock stability, aligning well with theoretical and experimental results.

Contribution

The paper presents a thermodynamically consistent kinetic model that captures phase-change and exotic behaviors across the entire phase diagram, including supercritical regimes.

Findings

Accurate simulation of van der Waals gas inversion line

Successful modeling of phase-change phenomena like evaporation and boiling

Excellent agreement with theoretical and experimental data

Abstract

We investigate a kinetic model for compressible non-ideal fluids [DOI:10.1103/PhysRevE.102.020103]. The model imposes the local thermodynamic pressure through a rescaling of the particles velocities, which accounts for both long- and short-range effects and hence full thermodynamic consistency. The model is fully Galilean invariant and treats mass, momentum and energy as local conservation laws. The analysis and derivation of the hydrodynamic limit is followed by the assessment of accuracy and robustness through benchmark simulations ranging from Joule-Thompson effect to a phase-change and high-speed flows. In particular, we show the direct simulation of the inversion line of a van der Waals gas followed by simulations of phase-change such as the one-dimensional evaporation of a saturated liquid, nucleate and film boiling and eventually,we investigate the stability of a perturbed strong shock front in two different fluid mediums. In all of the cases, we find excellent agreement with the corresponding theoretical analysis and experimental correlations. We show that our model can operate in the entire phase diagram, including super- as well as sub-critical regimes and inherently captures phase-change phenomena.