Recent advancements in large eddy simulations of compressible real gas flows

Abstract

This chapter explores some of the recent advancements in the field of computational fluid dynamics, specifically with respect to large eddy simulations. We start by introducing some fundamental concepts of scales of turbulent fluid flows. We then discuss the available simulation methods, major challenges of each method and the advantages of large eddy simulation (LES) over other methods. The focus of the chapter then shifts to real gas flows. Governing equations for LES of compressible flows and modifications for real gas flows are presented. Some of the filtering methods are discussed including physical space, Fourier space and proper orthogonal decomposition (POD) based filtering. The chapter then focuses on modeling of sub-filter / subgrid scale terms. A brief discussion of traditional modeling approaches is provided followed by a discussion of the current research and advancements. This discussion includes stochastic modeling using the filtered mass density function (FMDF) approach and machine learning based models for subgrid scales. For each method, a brief a background of the method, their applicability to different scenarios, their advantages, and disadvantages are presented.