What is Flamelet model combustion?

The flamelet approach for non-premixed combustion is based on the description of the turbulent flame as a collection of laminar flame elements embedded in a turbulent flow and interacting with it.

Who proposed laminar model?

The concept of ensemble of laminar flamelets was first introduced by Forman A. Williams in 1975, while the theoretical foundation was developed by Norbert Peters in the early 80s.

What is the scalar dissipation rate?

The mean scalar dissipation is a measure of the rate at which molecular diffusion processes lead to small-scale mixing in turbulent flows. It plays an important role in many theoretical descriptions [5], [6], [7], [8], [9] of the mean rate of chemical reaction in turbulent combustion, particularly when Da ≫ 1.

What causes laminar?

Laminar flow occurs when the fluid flows in infinitesimal parallel layers with no disruption between them. In laminar flows, fluid layers slide in parallel, with no eddies, swirls or currents normal to the flow itself. The laminar regime is ruled by momentum diffusion, while the momentum convection is less important.

Why is the laminar flamelet model so important?

The Laminar Flamelet Model is one of the methods of modelling turbulent combustions apart from SCRS, Eddy flamelet model and others. Combustion is a very important thermochemical process with significant material and aerodynamic implications and thus CFD modeling of combustion has become indispensable.

Is the flamelet approach an extension of the flame sheet model?

The flamelet approach can be considered as an extension of the “flame sheet” model which assumes infinitely fast chemical reaction such that the reaction zone is an infinitely thin interface.

How does the flamelet approach to chemistry work?

The flamelet approach relaxes the infinitely fast chemistry assumption by introducing the scalar dissipation rate as a parameter to describe the degree of departure from the equilibrium state.

How to calculate the density of a flamelet?

Given the distributions of both mixture fraction and the scalar dissipation rate, one can obtain density, temperature, and species concentrations from the flamelet library by a linear interpolation scheme. Combustion generated pollutants, such as NO, are formed near the reaction zone.