[divergence]

Hi all,

I've been working on a variety of burner applications where a more or less detailed description of combustion is desired. Based on empirical results, it has been noticed that the EDC model covers my needs pretty well. However, while experimenting with different sets of reaction equations, I have noticed that the constant values for time scale and volume fraction should be changed in order to gain realistic results.

Having roamed the enormous jungles that we call Internet in search of studies concerning these constants and their impact on the results, I have been left puzzled and slightly baffled of the lack of information concerning these constants. Therefore, I would like to ask this community for help. Has anyone better insight of these EDC parameters and their impact on calculations? Any study/dissertation/etc. would be most beneficial and appreciated highly.

My calculations concern mostly studying the combustion of natural gas (basically 100% methane) and they cover situations from premixed combustion to non-premixed combustion not forgetting cases where the gases are partially premixed.

[michall]

Hi,

If you mean Eddy Dissipation Concept (not model), then in general you should not change the constants, as they are strictly related to the turbulence model constants (e.g.. Ertesvag and Magnussen, Combust. Sci. Technol. (2000) vol. 159, pp 213-235)

There are some exception where people use modified constants in case of MILD combustion regime (e.g. De et al. Flow Turbul.Combust. (2011) vol. 87, pp 537-567 or more recent paper when they use functional expressions for the constants: Parente et al. Fuel (2016) vol. 163, pp 98-111). Whereas I work on other alternative solutions with the standard constant sets.