Experimental Research on the Co-deflagration Characteristics of a Mixture of Coal Powder and Corn Starch in an Air/methane Atmosphere

ABSTRACT

To investigate co-deflagration effect of a mixture of coal powder and corn starch, an air/methane atmosphere test was performed in a vertical explosion tube device and a 20-L spherical explosion device. Compared with pure coal powder and corn starch, the powder mixture undergoing deflagration in air was characterized by more uniform-distributed flame brightness, a more continuous flame structure, and less fluctuating flame propagation, approaching the fastest propagation velocity before mixing. Under the same mass concentration, the deflagration pressure of the powder mixture in methane atmosphere is related to the mixing proportion and is between the respective pressures of the two kinds of powder. P_m and (dP/dt)_m of the mixtures of methane and different powders show overall consistency with increasing equivalence ratios, however, different powders with the same equivalence ratio still differ in their characteristic deflagration parameters.

KEYWORDS:

• Powder mixture
• deflagration characteristics
• 20-L explosion device
• vertical tube
• flame propagation

Acknowledgments

The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China [grant numbers 51774280, 51174200].

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the the National Natural Science Foundation of China [51174200,51774280].