An Experimental Study on the Local Configuration of Premixed Turbulent Flame(<Special Issue>Recent Combustion Technology in Internal Combustion Engines)

In our previous works, the mean local burning velocity turned out to be changed from the original laminar burning velocity due to the preferential diffusion effect and it was found to be an important factor as dominating the turbulent burning velocity. In the present study, an attempt is made to investigate directly the local propagation characteristics of methane and propane premixed turbulent flames in the wrinkled laminar flame region. A laser tomography technique is used to obtain the local flame configuration and movement, and quantitative analyses are performed. As a result, the estimated local flame displacement velocities are found to be distributed over a wide range and to be dependent on the local curvature of the turbulent flame. In addition, its mean value of the methane mixture has a tendency to become larger as decreasing its equivalence ratio, whereas that of the propane mixture becomes smaller.