Study on the Resolution of Large-Eddy Simulations for Supersonic Jet Flows

TL;DR

This study investigates the impact of mesh and polynomial refinement on large-eddy simulations of supersonic jet flows, demonstrating improved accuracy with higher resolution and providing insights for future high-fidelity jet flow modeling.

Contribution

It systematically analyzes how discretization refinement affects LES accuracy for supersonic jets, using high-resolution simulations with up to 410 million DOFs.

Findings

Higher resolution improves agreement with experimental data.

Refinement leads to better velocity fluctuation predictions.

Data guides future LES of similar jet flows.

Abstract

The present study is concerned with large-eddy simulations (LES) of supersonic jet flows. The work addresses, in particular, the simulation of a perfectly expanded free jet flow with an exit Mach number of 1.4 and an exit temperature equal to the ambient temperature. Calculations are performed using a nodal discontinuous Galerkin method. The present effort studies the effects of mesh and polynomial refinement on the solution. The present calculations consider computational meshes and polynomial orders such that the number of degrees of freedom (DOFs) in the solution ranges from 50 to 410 million. Mean velocity results and root mean square (RMS) values of velocity fluctuations indicate a better agreement with experimental data as the resolution is increased. The generated data provide a good understanding of the effects of increasing the discretization refinement for LES calculations of jet flows. The present results can guide future simulations of similar flow configurations.