Heat flux from a diffusion flame leading edge to an adjacent surface

We examine the attachment of diffusion flames (DFs) near cold, chemically i nert surfaces. A two-dimensional model based on the examination of the diff usion flame leading edge is constructed. Two matching procedures give separ ate models, the simplified model and the detailed model. A quench-distance formula is produced by the simplified model, which correlates the numerical results in terms of the reduced Damkohler number. The detailed model predi cts quench distances in good agreement with numerical solutions for the sto ichiometrics chosen herein. Heat fluxes to the cold adjacent surface from t he flame tip are evaluated from the model. A formula is derived which predi cts the flame heat flux to the surface beneath the flame leading edge. The final form of this formula contains a coefficient function of stoichiometry , which was derived by matching the theoretical and numerical predictions. (C) 1999 by The Combustion Institute.