Energy attenuation behavior on propane-air premixed combustion on account of nonmetallic spherical spacers in confined space with two perforated plates

Energy attenuation behavior on propane premixed combustion on account of nonmetallic spherical spacers (NSSs) was investigated in a constant volume combustion bomb with two accelerative perforated plates. The flame evolution process is captured by a photography device with schlieren. Energy attenuation effects of NSSs were explored on flame propagation, overpressures, and pressure oscillation. Normal combustion accomplished with flame acceleration, jet autoignition, deflagration, and weak detonation is observed, respectively. NSSs show a good energy attenuation effect on propane normal combustion, jet autoignition, and deflagration evolution behavior, however, during the evolution of weak detonation, the attenuation effect is relatively weak. The mean velocities difference, as well as explosion overpressure decay rate caused by NSSs, decreases from (45.70 m/s and 26.48%) to (2.70 m/s and 18.15%) when the initial pressure increases from 0.1 to 0.5 MPa, namely, attenuation effect of NSSs on propane explosion decreases with increasing initial pressure. Energy attenuation effects of nonmetallic spherical spacers (NSSs) are explored on flame propagation, overpressure, and pressure oscillation. NSSs show good energy attenuation effects on propane normal combustion, jet autoignition, and deflagration evolution behavior. During the evolution of weak detonation, the attenuation effect of NSSs is relatively weak. The attenuation effect of NSSs is quantitatively analyzed by combustion intensity (pressure oscillation). This research provides theoretical support for the effective suppression of gas explosion accidents under different conditions and for developing fire-retardant merchandises.image