HYDROXYL CONCENTRATION PROFILES IN A BOUNDARY-LAYER COMPOSED OF COMBUSTION PRODUCTS

A study is made of the behavior of hydroxyl near a cold electrode in a flow of products from the combustion of propane in air at atmospheric pressure. The method of resonance laser fluorescence is used to obtain profiles of hydroxyl concentration for different flame compositions and different surface materials (copper, fluoroplastic). Good agreement is obtained with the results of a detailed kinetic calculation. It is seen that there is an increase in the thickness of the concentration boundary layer for flames with an excess of fuel. The boundary conditions are found to have relatively little effect on hydroxyl concentration profiles at distances from the surface greater than 0.25 mm.