Experimental study of the syngas/air mixtures explosion characteristics in a semi-open duct containing copper foam

Abstract

Syngas, a low-carbon, clean, and hydrogen-rich fuel, is gaining increasing attention and plays a critical part in global energy transition. However, the potential explosion risk limits its applications. Therefore, investigating methods to suppress explosion flame propagation is crucial for ensuring the safe utilization of syngas. This study investigated the flame propagation characteristics of syngas/air mixtures explosion in a semi-open duct containing copper (Cu) foam. The study focused on the coupling effect of five Cu foams with different pores per inch (PPI) and hydrogen volume fraction. Experimental results indicated that the flame propagation process in a semi-open duct containing the Cu foam exhibited two typical phenomena. The Cu foam with appropriate parameters successfully quenched syngas/air mixtures explosion flame. The Cu foam had a small effect on the upstream flame propagation kinetic characterization. When PPI ≥ 30, the flame propagation velocity was suppressed. When PPI < 30, the presence of Cu foam promoted the flame propagation. When PPI < 30, the overpressure increased compared with the case without the Cu foam, while the results were the opposite when PPI ≥ 30. The maximum overpressure and flame velocity were obtained when PPI = 20. Moreover, the study analyzed the retardant mechanism of Cu foam against the syngas/air mixtures explosion flame. These findings may provide valuable insights for the design of flame arrestors and improving the safety in the utilization of hydrocarbon fuels.