Constrained large-eddy simulation of wall-bounded compressible turbulent flows

Abstract

A constrained large-eddy simulation (CLES) approach is developed for wall-bounded compressible turbulent flows based on its incompressible analogue [Chen et al., “Reynolds-stress-constrained large-eddy simulation of wall-bounded turbulent flows,” J. Fluid Mech. 703, 1–28 (2012)]. In the new CLES approach, both the subgrid-scale (SGS) stress and the SGS heat flux are decomposed into an averaged part and a fluctuating part in the near-wall region with the mean SGS stress and heat flux constrained by prescribed Reynolds stress model and turbulent heat flux model, respectively. The Smagorinsky SGS models are employed to approximate the SGS stress and heat flux in the remaining region of the flow domain. The present CLES method is validated by simulating the compressible turbulent channel flows at various Reynolds numbers and Mach numbers. The mean velocity profiles, mean temperature profiles, and other statistical quantities and turbulent structures are obtained and well compared among the present approach, direct numerical simulation (DNS), detached eddy simulation (DES) and traditional large eddy simulation (LES). The results demonstrate that the dual constraint of Reynolds stress and turbulent heat flux plays a non-trivial role in enhancing the ability of LES for wall-bounded compressible flows. In addition, the Reynolds and Mach numbers effects on the mean and statistical quantities as well as the turbulence structures are investigated using the proposed CLES method. The main conclusions are in very good agreement with those drawn by other authors using DNS method. All the results manifest that the present CLES technique is an encouraging and useful tool for wall-bounded compressible turbulent flows.

Constrained Large-Eddy Simulation for Aerodynamics

“…These model coefficients can be prescribed empirically or calculated instantaneously through a dynamic procedure. For details of the derivation of the DC-SGS models, readers are referred to the article by Chen et al [1] for incompressible flow and the one by Jiang et al [6] for compressible flow. In the rest region of the flow domain, traditional Smagorinsky models for the SGS stress and SGS heat flux can be utilized [9].…”

“…(1)- (4). Considering that both the Reynolds stress and the Reynolds heat flux are poorly estimated by traditional LES approaches in the near-wall region of wall-bounded compressible flows, Jiang et al introduced a dual-constraint SGS (DC-SGS) model for LES of such flows [6]. The formulations of the DC-SGS models are reviewed briefly as follows.…”

“…It is found that the RS-CLES approach successfully combines the positive points both from traditional LES and DES, and can accurately predict the mean quantities and flow structures of both attached and detached flows. Recently, Jiang et al [6] extended the RS-CLES method and introduced a Reynolds heat flux constrained model for the SGS heat flux required in LES of wall-bounded compressible turbulent flows. The performance of the CLES method for wall-bounded compressible flows is superior to those of traditional LES and DES methods when they are compared in the prediction of compressible turbulent channel flow [6].…”

“…Recently, Jiang et al [6] extended the RS-CLES method and introduced a Reynolds heat flux constrained model for the SGS heat flux required in LES of wall-bounded compressible turbulent flows. The performance of the CLES method for wall-bounded compressible flows is superior to those of traditional LES and DES methods when they are compared in the prediction of compressible turbulent channel flow [6]. In this paper, the compressible CLES technique is tested and validated a posteriori in the simulations of both attached and detached flows in order to ascertain its capability to predict complex and wall-bounded compressible turbulent flows on relatively coarse grids.…”

Joint-constraint model for large-eddy simulation of helical turbulence

“…[46], the variation process under an SGS dissipation constraint is helpful in improving the performance of a mixed dynamic model for simulation of driven and decaying isotropic turbulence. It was also shown that the inclusion of the near-wall Reynolds stress (and heat flux) constraint(s) in the SGS modeling allows the LES technique to simulate wall-bounded turbulent flows at moderate grid resolutions with promising accuracy [47,48]. Although the physical mechanism of the interplay between energy and helicity cascades still remains unclear, the effect of helicity has been taken into account for turbulence modeling.…”