Abstract
Spherically propagating laminar and turbulent flames at elevated pressures in a large volume bomb were studied using ethanol-air mixtures. Experiments were carried out at the equivalence ratio 0.8 1.0 and 1.4 varying the initial pressure from 0.10 to 0.50 MPa. Turbulence intensity of the mixture was 0.80 and 1.59 m/s. The unstretched laminar burning velocity, U_l decreased as the initial pressure increased. The ratio of the turbulent burning velocity to U_l increased with increasing the ratio of turbulence intensity to ui and turbulence Karlovitz number. This burning velocity ratio was large for rich flames. Thermo-diffusive effects might be more influential to rich ethanol flames because of the small Lewis number. This burning velocity ratio was also found to increase with increasing initial pressure.