A comparative study on the turbulent explosion characteristics of syngas between CO-enriched and H2-enriched

Abstract

Syngas, containing mostly CO and H2, has variant explosion properties for the specific contents. For a further understanding, a comparative study on the turbulent explosion characteristics of syngas between CO-enriched (the mole ratio of CO was 70%) and H2-enriched (the mole ratio of H2 was 70%) were conducted at different equivalence ratios (φ, from 0.4 to 3.0) and turbulent intensities (u'rms, from 0 to 1.309 m/s). The peak value of maximum explosion pressure (pmax) was attained in the stoichiometric explosion of H2-enriched syngas but in fuel-rich explosion of the CO-enriched, the growth extents of pmax seemed more sensitive to u'rms for H2-enriched syngas compared to CO-enriched syngas. The lowest values of explosion duration (tc) was attained in fuel-rich explosions for both CO-enriched and H2-enriched syngas but different corresponding φ to the lowest tc, the phenomena were analyzed from the aspects of ignition delay time, laminar burning velocity, intrinsic instabilities, and flame/turbulence interaction. Finally, the pressure rising was comparatively observed, the maximum pressure rise rate ((dp/dt)max) expressed more similar variation regulations to tc rather than pmax, which meant flame propagation speed plays a more important role on the evolution of pressure rising.