Measurement of laminar burning velocity of dimethyl ether-air premixed mixtures

Measurement of laminar burning velocity of dimethyl ether-air mixtures was taken under different initial pressures and equivalence ratios using a constant volume bomb and high-speed schlieren photography. The stretched laminar burning velocity increases with the increase of stretch rate. At equivalence ratio of 1.0, low initial pressure gives high stretched flame speed. At initial pressure less than 0.1 MPa, the stoichiometric mixture gives the higher value of stretched flame speed than those at phi = 1.2 and phi = 0.8. The Markstein numbers decrease with the increase of equivalence ratio, and this reveals that lean mixture will maintain higher stability of flame front surface than that of rich mixture in dimethyl ether-air premixed flames. (C) 2007 Elsevier Ltd. All rights reserved.