Stratified Turbulence

Summary

The focus of this research effort is on development of novel physics-based modeling approaches for large-eddy simulation (LES) of stratified turbulent flows, which are observed in engineering and natural systems.

Support

The work was supported by Office of Naval Research (ONR) while Dr. Ranjan worked as a research staff at CCL@GT. Currently, development and application work occurs through a collaborative research effort between FCM@UTC and CCL@GT.

Test Cases

• Turbulent Channel
• Taylor Green Vortex
• Axisymmetric Wake

Computational Approaches

Following LES modeling approaches have been established in the in-house incompressible flow solver referred to as MINCLES, and are being evaluated on different test cases:

• Dynamic Smagorinsky Model
• Scale Similar Model
• Mixed Model
• One-Equation Dynamic Model
• Two Level Simulation Model
• Integral Length Scale Approximation Model

Publications

1. S. Thompson, and R. Ranjan, “On the effects of differential diffusion and equation of state in stably stratified turbulent channel flow”, 75th Annual Meeting of the APS Division of Fluid Dynamics, November 20-22, 2022; Indianapolis, IN, USA.
2. R. Ranjan, S. Kim, and S. Menon, “Hybrid Two-Level and Large-Eddy Simulation of the Wake of a Towed Sphere in Stably Stratified Fluid”, 34th Symposium on Naval Hydrodynamics, June 26 – July 1,  2022; Washington, DC, USA.
3. R. Ranjan, M. Venkataswamy, and S. Menon, “Dynamic one-equation-based subgrid model for large-eddy simulation of stratified turbulent flows“, Physical Review Fluids, 5 (6), 064601, 2020.
4. M. Venkataswamy, R. Ranjan, and S. Menon, “Investigation of effects equation of state and differential diffusion on fully developed stratified turbulent channel flow”, 71st Annual Meeting of the APS Division of Fluid Dynamics, November 18–20, 2018; Atlanta, GA, USA.
5. R. Ranjan, and S. Menon, “LES of stratified turbulent wake with temperature and salinity dependent density stratification”, 70th Annual Meeting of the APS Division of Fluid Dynamics, November 19-21, 2017, Denver, CO, USA.