Toward Meshless Turbulent Flow Simulation: LES-Integrated Vortex Particle Method

TL;DR

This paper introduces a meshless vortex particle method integrated with a dynamic LES model for simulating turbulent incompressible flows, emphasizing minimal auxiliary computation and accurate flow diagnostics.

Contribution

It presents a novel meshless vortex particle method with a dynamic LES model relying solely on Lagrangian data and high-order kernels for turbulence simulation.

Findings

Accurately captures flow kinematics with sparse particles.

Effectively models energy, helicity, and enstrophy conservation.

Flow stabilization depends on particle regularization after instabilities occur.

Abstract

Recent developments in vortex particle methods for simulating three-dimensional incompressible flows are presented. A lightweight, dynamic Large-Eddy Simulation model is tested, featuring a dynamic procedure that relies solely on Lagrangian information and requires minimal auxiliary computation to update the model constant. The method employs a high-order algebraic kernel which enables direct, analytical expressions for conservation laws, the strain-rate tensor, and quadratic velocity diagnostics. Viscous diffusion is modeled using the core-spreading technique. The particle method is assessed with respect to kinematics and the conservation of energy, helicity, and enstrophy in vortex ring and leapfrogging vortex ring scenarios, both unperturbed and perturbed. The results indicate that the kinematics and flow diagnostics are accurately captured using relatively sparse particle distributions, effectively resolving the dynamics of the unstable flow phase. However, after the onset of instabilities, the sub-grid-scale methodology becomes strongly dependent on particle regularization to stabilize the flow solution.