Experimental investigation on micro-dynamic behavior of gas explosion suppression with SiO2 fine powders

To study the effect of inert dust on gas explosion suppression mechanism, SiO2 fine powders were sprayed to suppress premixed CH4-Air gas explosion in a 20 L spherical experimental system. In the experiment, high speed schlieren image system was adopted to record explosion flame propagation behaviors, meanwhile, pressure transducers and ion current probes were used to clearly record the explosion flame dynamic characteristics. The experimental results show that the SiO2 fine powders suppressed evidently the gas explosion flame, and reduced the peak value of pressure and flame speed by more than 40 %. The ion current result shows that the SiO2 super fine powders were easy to contact with and absorb free radicals near the combustion reaction region, which greatly reduced the combustion reaction intensity, and in turn influenced the flame propagation and pressure rising.