Turbulent transport processes in swirling recirculating nonpremixed flames
Abstract
Turbulent transport processes typical of swirling recirculating flows, including those with chemical reaction, are analyzed and discussed based upon laserDoppler measurements of mean and turbulent velocity characteristics. For the combusting flows, the results encompass the study of a nonpremixed flame with a heat load of 350 kW and include mean temperature measurements. The results show that although combustion does not alter the mean flow pattern, it increases mean shear and curvature, resulting in increased turbulence levels and anisotropy throughout the flow. This is associated with large scale motions with a predominant frequency, although their contribution to the timeaverage turbulent kinetic energy is shown to be small. Inspection of the terms in the conservation equations for the turbulent stresses have allowed to quantify the extent up to which the interaction of normal stresses and normal strains influence the flow and suggest the likely magnitude of turbulent diffusion and dissipation.
 Publication:

8th Symposium on Turbulent Shear Flows, Volume 2
 Pub Date:
 1991
 Bibcode:
 1991tsf.....2...31D
 Keywords:

 Combustible Flow;
 Flame Propagation;
 Recirculative Fluid Flow;
 Swirling;
 Transport Theory;
 Turbulent Flow;
 Combustion Physics;
 Flow Geometry;
 Flow Velocity;
 Laser Doppler Velocimeters;
 Reacting Flow;
 Reynolds Stress;
 Fluid Mechanics and Heat Transfer