Large eddy simulations of turbulent compressible supersonic jet flows using discontinous Galerkin methods

TL;DR

This paper employs discontinuous Galerkin methods to perform large eddy simulations of supersonic jet flows, demonstrating that higher resolution improves accuracy and that initializing high-order simulations with lower-order results reduces computational costs.

Contribution

It introduces a strategy to efficiently perform high-order LES of supersonic jets by using lower-order simulations for initialization, saving computational resources.

Findings

Higher resolution simulations align better with experimental data.

Using lower-order simulations for initialization reduces high-order simulation time by about 95%.

Jet lipline behavior remains inconsistent across resolutions.

Abstract

In this work, a discontinuous Galerkin scheme is employed to perform LES simulations of supersonic jet flows. A total of four simulations are performed with different meshes and order of accuracy. The number of degrees of freedom from the simulations varies from 50 x 106 to 400 x 106. The results indicate that by increasing the resolution of simulation, in general, the results got closer to experimental data. The jet lipline is the only region in which this behavior is not observed. It investigated a procedure of using lower-order simulations to initialize high-order simulations and consequently reduce the total time of the simulation using high-order schemes. This strategy is successful and allows to perform high-order simulations with only 5% more computational effort than a complete second-order simulation.