Generalization of the Flame Stretch Concept for Stationary Premixed Flames

摘要

The concept of flame stretch is generalized for the case of stationary premixedflames with a finite thickness. It is shown that the analysis results in additional contributions to the stretch rate due to changes in the flame thickness and due to density variations along the flame. More general expressions are derived that describe the effect of stretch on variations in scalar quantities, such as the enthalpy. These expressions are used to determine local variations in the flame temperature. Finally, the different contributions to the total stretch rate are numerically computed for the flame tip of a two-dimensional Bunsen flame as illustration.