Experimental study on effect of dilute coal dust on gas explosion pressure/flame evolution process

To understand the effect of dilute coal dust on a gas explosion, a cylindrical chamber is employed to study the explosion pressure and flame morphology changes of dilute coal dust-gas hybrid mixtures. The experimental results show that the maximum explosion pressure first increases and subsequently decreases with the increase in the coal dust concentration at methane volume fractions of 9.5% and 8.0%. At a methane volume fraction of 6.5%, the presence of diluted coal dust typically shows a suppression effect. The initial effect of the coal dust on a spherical flame is mainly to reduce both the stretching velocity and critical radius, allowing the flame to earlier change from a laminar smooth state to a cellular wrinkled state. The research results can provide an experimental basis for further exploring the gas coal dust mixed explosion mechanism and the construction of a chemical kinetic mechanism