A Preliminary Research on Turbulent Flame Propagation Combustion Modeling Using a Direct Chemical Kinetics Model

A pseudo-compressibility method for zero Mach number turbulent reactive flows with heat release is combined with an unstructured finite volume hybrid grid scheme. The spatial discretization is based on an overlapped cell vertex approach. An infinite freely planar flame propagating into a turbulent medium of premixed reactants is considered as a test case. The recourse to a flamelet combustion modeling for which the reaction rate is quenched in a continuous way ensures the uniqueness of the turbulent flame propagation velocity. To integrate the final form of discretized governing equations, a three-stage hybrid time-stepping scheme is used and artificial dissipation terms are added to stabilize the convergence path towards the final steady solution. The results obtained with such a numerical procedure prove to be in good agreement with those reported in the literature on the very same flow geometry. Indeed, the flame structure as well as its propagation velocity are accurately predicted thus confirming the validity of the approach followed and demonstrating that such a numerical procedure will be a valuable tool to deal with complex reactive flow geometries.

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A Continuous Multicomponent Fuel Flame Propagation and Chemical Kinetics Model

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4000267 ◽

2010 ◽

Vol 132 (7) ◽

Cited By ~ 5

Author(s):

Shiyou Yang ◽

Rolf D. Reitz

Keyword(s):

Chemical Kinetics ◽

Flame Propagation ◽

Adaptive Method ◽

Mixture Composition ◽

Kinetics Model ◽

Fuel Vapor ◽

Vapor Mixture ◽

Fuel Model ◽

Primary Reference ◽

The Mean

A continuous multicomponent fuel flame propagation and chemical kinetics model has been developed. In the multicomponent fuel model, the theory of continuous thermodynamics was used to model the properties and composition of fuels such as gasoline. The difference between the current continuous multicomponent fuel model and previous similar models in the literature is that the source terms contributed by chemistry in the mean and the second moment transport equations have been considered. This new model was validated using results from a discrete multicomponent fuel model. In the flame propagation and chemical kinetics model, five improved combustion submodels were also integrated with the new continuous multicomponent fuel model. To consider the change in local fuel vapor mixture composition, a “primary reference fuel (PRF) adaptive” method is proposed that formulates a relationship between the fuel vapor mixture PRF number (or research octane number) and the fuel vapor mixture composition based on the mean molecular weight and/or variance of the fuel vapor mixture composition in each cell. Simulations of single droplet vaporization with a single-component fuel (iso-octane) were compared with multicomponent fuel cases.

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A Continuous Multi-Component Fuel Flame Propagation and Chemical Kinetics Model

ASME 2009 Internal Combustion Engine Division Spring Technical Conference ◽

10.1115/ices2009-76076 ◽

2009 ◽

Author(s):

Shiyou Yang ◽

Rolf D. Reitz

Keyword(s):

Chemical Kinetics ◽

Flame Propagation ◽

Adaptive Method ◽

Mixture Composition ◽

Kinetics Model ◽

Fuel Vapor ◽

Vapor Mixture ◽

Fuel Model ◽

The Mean ◽

The Difference

A continuous multi-component fuel flame propagation and chemical kinetics model has been developed. In the multicomponent fuel model, the theory of continuous thermodynamics was used to model the properties and composition of fuels such as gasoline. The difference between the current continuous multi-component fuel model and previous similar models in the literature is that the source terms contributed by chemistry in the mean and the second moment transport equations have been considered. This new model was validated using results from a discrete multi-component fuel model. In the flame propagation and chemical kinetics model, five improved combustion sub-models were also integrated with the new continuous multi-component fuel model. To consider the change of local fuel vapor mixture composition, a “PRF adaptive” method is proposed that formulates a relationship between the fuel vapor mixture PRF number (or octane number) and the fuel vapor mixture composition based on the mean molecular weight and/or variance of the fuel vapor mixture composition in each cell. Simulations of single droplet vaporization with a single-component fuel (iso-octane) were compared with multi-component fuel cases.

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