Search Results

The influence of pressure on spherically propagating premixed turbulent flames was examined with experiments carried out using a constant volume fan-stirred combustion vessel. The effects of mixture strength and turbulence intensity on the propagation and quench of turbulent flames were studied for mixture pressures of 0.10 to 0.50 MPa. Two mechanisms of quench were observed and are discussed for lean and rich flames. Possible correlations of turbulent burning velocity were developed in terms of Lewis and turbulence Reynolds numbers.

Syngas, is an alternative fuel consisting mainly of hydrogen and carbon monoxide in various proportions. An understanding of the effects of the varying constituents on the combustion characteristics is important for improvement of the thermal efficiency of syngas-fueled engines. The effects of hydrogen concentration and mixture pressure on the turbulent burning velocity of outwardly propagating stoichiometric flames of hydrogen-carbon monoxide-air were studied in a constant volume fan-stirred combustion chamber at a constant mixture temperature of 350 K. The mole fraction of hydrogen in the binary fuel was varied from 0 to 1.0, at mixture pressures of 0.10, 0.25 and 0.50 MPa. The turbulence intensity was kept constant at 3.27 m/s. For fixed mixture pressures, it was found that the turbulent burning velocity increased with an increase in hydrogen fraction primarily due to increase in the unstretched laminar burning velocity.