EFFECTS OF MICRO-MIXING IN GAS-PHASE TURBULENT JETS

Scaler mixing in turbulent jets is modeled using a hybrid Monte Carlo PDF method which solves for the joint velocity-scaler PDF. Molecular s calar mixing is modeled by: Interaction by Exchange with the Mean, Coa lescence/Dispersion (C/D), Binomial Langevin and Mapping Closure model s. The concentration field statistics adopt a self-similar solution al ong rays emerging from the jets virtual origin. Predicted PDF's of the normalized concentration are compared to measurements. All mixing mod els yield good agreement with the measurements at all radial and axial positions. The C/D model gives the best results close to the centerli ne but at the edge of the jet, the model predicts unrealistic PDF shap es. (C) 1998 Published by Elsevier Science Inc. All rights reserved.