Turbulence-Chemistry Interactions Model Reference

Turbulence-chemistry interactions require additional modeling, as well as RANS or LES modeling, to allow chemical reactions in thin reaction zones to be solved.

Turbulence-Chemistry Interactions Reference


Model Names and Abbreviations	Eddy Dissipation Concept		EDC
	Laminar Flame Concept		LFC
	Thickened Flame Model		TFM
	Turbulent Flame Speed Closure See Turbulent Flame Speed Closure (Complex Chemistry) Model Reference		TFC
Theory	See Complex Chemistry.
Provided By	[physics continuum] > Models > Turbulence Chemistry Interactions
Example Node Path	Continua > Physics 1 > Models > Eddy Dissipation Concept
Requires	Material: Multi-Component Gas or Multi-Component Liquid Reaction Regime: Reacting Reactive Flow: Reacting Species Transport Reacting Species Models: Complex Chemistry
Properties	none
Activates	Model Controls (child nodes)	EDC only: EDC Fine Structure Time Factor EDC Fine Structure Length Factor When modeling Steady simulations, the Eddy Dissipation Concept > Acceleration Factor or Laminar Flame Concept > Acceleration Factor node appears. See Acceleration Factor Properties.
	Field Functions	EDC Fine Structure Length Fraction, EDC Fine Structure Time, EDC Mean Reaction Rate Ratio. (There are no LFC-related field-functions). See Field Functions.

EDC Fine Structure Time Factor

Allows you to specify the fine structure (flamelet) time factor, $C_{t}$ in Eqn. (1164) as a scalar profile.

EDC Fine Structure Length Factor

Allows you to specify the fine structure (flamelet) length factor, $C_{l}$ in Eqn. (3413) as a scalar profile.

Acceleration Factor Properties

Acceleration Factor: Setting a value of 1.0 indicates that the species source term is fully explicit which results in unstable, but fast, convergence. When a value of 0.0 is set, the species source term is taken as fully implicit which results in stable, but slow, convergence. In practice, you set a value between 0.0 and 1.0 which provides the best convergence when using default Under Relaxation Factor values.

Turbulence-Chemistry Interactions Field Functions

Complex Chemistry with EDC

The following field functions are made available when using the Complex Chemistry and Eddy Dissipation Concept (EDC) models:

EDC Fine Structure Length Fraction: $C_{l} {(\frac{υ T}{L^{2}})}^{0.25}$ in Eqn. (3413).
EDC Fine Structure Time: The fine structure (flamelet) region residence time, $τ$ in Eqn. (3414).
EDC Mean Reaction Rate Ratio: The ratio $f$ that is calculated by Eqn. (3413) which is used to modify the chemical reaction source term in Eqn. (3412).