English

Turbulent Flame Speeds of G-equation Models in Unsteady Cellular Flows

Pattern Formation and Solitons 2012-10-08 v1 Numerical Analysis Fluid Dynamics

Abstract

We perform a computationl study of front speeds of G-equation models in time dependent cellular flows. The G-equations arise in premixed turbulent combustion, and are Hamilton-Jacobi type level set partial differential equations (PDEs). The curvature-strain G equations are also non-convex with degenerate diffusion. The computation is based on monotone finite difference discretization and weighted essentially nonoscillatory (WENO) methods. We found that the large time front speeds lock into the frequency of time periodic cellular flows in curvature-strain G-equations similar to what occurs in the basic inviscid G-equation. However, such frequency locking phenomenon disappears in viscous G-equation, and in the inviscid G-equation if time periodic oscillation of the cellular flow is replaced by time stochastic oscillation.

Keywords

Cite

@article{arxiv.1210.1671,
  title  = {Turbulent Flame Speeds of G-equation Models in Unsteady Cellular Flows},
  author = {Yu-Yu Liu and Jack Xin and Yifeng Yu},
  journal= {arXiv preprint arXiv:1210.1671},
  year   = {2012}
}