Investigation of axisymmetric buoyant turbulent diffusion flames: Turbulence properties and concentrations of major species

Earlier measurements of mean velocities and temperatures in buoyant, turbulent, axisymmetric methane diffusion flames burning in still air were extended to include measurements of fluctuating velocities and mean species concentrations (CH4, N2, O2, CO2, H2O, CO and H2). These measurements, as well as existing measurements in turbulent propane diffusion flames, were employed to evaluate differential models of the process including: (1) a base k-epsilon-g model where effects of buoyancy are only considered in the governing equations for mean quantities; and (2) an extended k-epsilon-g model where buoyancy is also considered in the governing equations for turbulence quantities. Two methods for determining state relationships (the variation of scalar properties as a function of mixture fraction) used in these models were also evaluated.