Using approximate inertial manifold approach to model turbulent non-premixed combustion
Abstract
The theory of inertial manifolds (IM) is used to develop reduced-order models of turbulent combustion. In this approach, the dynamics of the system are tracked in a low-dimensional manifold determined in-situ without invoking laminar flame structures or statistical assumptions about the underlying turbulent flow. The primary concept in approximate IM (AIM) is that slow dominant dynamical behavior of the system is confined to a low-dimension manifold, and fast dynamics respond to the dynamics on the IM instantaneously. Decomposition of slow/fast dynamics and formulation of an AIM is accomplished by only exploiting the governing equations. Direct numerical simulations (DNS) of initially non-premixed fuel-air mixtures developing in forced isotropic turbulence have been carried out to investigate the proposed model. Reaction rate parameters are varied to allow for varying levels of extinction and reignition. The AIM performance in capturing different flame behaviors is assessed both a priori and a posteriori. It is shown that AIM captures the dynamics of the flames including extinction and reignition. Moreover, AIM provides scalar dissipation rate, mixing time for reactive scalars, and closures for nonlinear terms without any additional modeling. The AIM formulation is found promising, and provides a new approach to modeling turbulent combustion.
Keywords
Cite
@article{arxiv.2103.12299,
title = {Using approximate inertial manifold approach to model turbulent non-premixed combustion},
author = {Maryam Akram and Venkat Raman},
journal= {arXiv preprint arXiv:2103.12299},
year = {2021}
}
Comments
Published in Physics of Fluids. However, this version shows correct figure legends, which are absent from the published version due to typesetting issues. This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article may be found at https://doi.org/10.1063/5.0039402