SANDIA Flame D

Application Challenge AC2-09 © copyright ERCOFTAC 2024

Overview of CFD Simulations

SIMULATION CASE CFD1

Solution Strategy

Computational Domain

Boundary Conditions

Application of Physical Models

In the most general case modeling of the combustion processes is very expensive computationally since together with the solution of the flow field it requires solution of additional transport equations for particular N species (e.g. CO, CO₂, H₂O, H₂, etc.) produced in chemical reactions. The transport equations for species have the following form:

{\frac {\partial \rho Y_{k}}{\partial t}}+{\frac {\partial \rho u_{i}Y_{k}}{\partial x_{i}}}={\frac {\partial }{\partial x_{i}}}\left(\rho D_{k}{\frac {\partial Y_{k}}{\partial x_{i}}}\right)+{\dot {\omega _{k}}}\quad k=1,2,\dots ,N\qquad (1)

where

$\rho$	is the density
$u_{i}$	is the velocity component
$Y_{k}$	is the mass fraction of species $k$
${\dot {\omega _{k}}}$	is the reaction rate (speed of creation/destruction of a given species)
$D_{k}$	is the diffusion coefficient usually taken the same (denoted by $D$ ) for
	each species and defined as $\rho D=\mu /Pr$ , where $\mu$ is the molecular viscosity and $Pr$ is the Prandtl number.