- Author
-
Baum, H. R.
|
Rehm, R. G.
|
Gore, J. P.
- Title
- Transient Combustion in a Turbulent Eddy.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
Maryland Univ., College Park
- Book or Conf
- Combustion Institute, Symposium (International) on Combustion, 23rd. July 22-27, 1990,
Combustion Institute, Pittsburgh, PA,
Orleans, France,
715-722 p.,
1991
- Keywords
-
combustion
|
turbulent combustion
|
diffusion flames
|
formulations
|
combustion models
|
mathematical models
|
reaction models
- Abstract
- A mathematical model of a local transient diffusion flame generated by mixing in a turbulent eddy is presented. It is intended ultimately as a computational "molecule" to be imbedded in numerical simulations of large scale reacting flows. The specific objective of the present analysis is to account explicitly for the modification of the local velocity field induced by the heat generation process. An "idealized" single step irreversible reaction model and a model treating the effects of real chemistry within the laminar flamelet approximation are considered. The convection diffusion equation for the mixture fraction and the mass conservation equation are analyzed using the experimental observation that specific volume is a piecewise linear function of mixture fraction. A Cole-Hopf transformation is used to reduce this equation to an incompressible form in terms of a new "pseudo mixture fraction" which can be related to all scalar properties using measured or idealized state relationships. Seven different fuels have been studied. Sample results for two of these are presented.