Laminar burning velocities for mixtures of methanol and air at elevated temperatures

In this paper, centrally ignited, spherically expanding flames have been measured using the schlieren photography technique to determine the influence of the fuel/air equivalence ratio and initial temperature on the laminar burning velocities of methanol–air mixtures. The flames are recorded by a high speed camera and then analyzed to deduce the flame speed. The stretch imposed on the spherical flame front has been explored experimentally. As a consequence, the unstretched laminar burning velocities of methanol–air flames are derived. The Markstein lengths have been determined in terms of characterizing the influence of flame stretch, and an empirical correlation in the function form of ul=ulo(Tu/Tu0)αTul=ulo(Tu/Tu0)αT is obtained to formulate the laminar burning velocity dependencies on the equivalence ratio and initial temperature. Comparisons of this empirical correlation for burning velocities with the results reported previously have been implemented over wide temperature and equivalence ratio ranges, and good agreements with them give validation of the present study.