Summary
The focus of this research effort is on assessment and application of non-linear reduced order modeling (ROM) techniques for LES of chemically reacting turbulent flows. The ROM approach is based on a Galerkin projection technique where proper orthogonal decomposition (POD) modes are used as basis functions and discrete empirical interpolation method is used for efficiently computing the nonlinear terms.
Support
The work was supported by Air Force Office of Scientific Research (AFOSR) while Dr. Ranjan worked as a research staff at CCL@GT. Currently, the development and application work occurs through a collaborative research effort between FCM@UTC and CCL@GT. Dr. Ranjan is currently supported for this effort through the CEACSE Faculty Initiation and Career Opportunity Grant at UTC.
Test Cases
- 1D Complex Ginzbug Landau Equation
- 1D Freely Propagating Laminar Premixed Flame
- 3D Turbulent Premixed Flame
- Longitudinal Combustion Instability in CVRC
- Premixed Combustion in LM6000
Computational Approaches
The intrusive ROM approach has been implemented within the well-established multi-physics solver referred to as LESLIE (developed within CCL@GT) and another in-house research code referred to as AVF-LESLIE. Currently, two approaches have been implemented:
- POD based ROM: The approach only relies on Galerkin projection using the POD modes as basis function. This approach is primarily suitable for linear problems as for nonlinear problems the computational cost still depends upon the size of employed computational mesh.
- POD-DEIM based ROM: The approach offers a significant reduction in computational cost compared to POD based ROM for nonlinear problems.
Publications
- R. Ranjan, and S. Menon, “Application of Nonlinear Reduced Order Modeling Strategy for Large Eddy Simulation of Chemically Reacting Turbulent Flows”, AIAA-2020-2140.
- R. Ranjan, S. Menon, and R. Munipalli, “Reduced Basis Modeling of Single-Element Subscale Rocket Combustors”, AIAA-2018-4871.