Investigation on the suppression and enhancement mechanism of Fe(C5H5)2 on hydrogen explosion

The safe development of hydrogen industry requires high-efficiency explosion suppression material. In this research, Fe(C 5 H 5 ) 2 is demonstrated to have better suppression effect compared with traditional powder materials, due to a coupling mechanism of oxidizer competing and radical annihilating. Fe(C 5 H 5 ) 2 and its decomposition substances could contribute to the consumption of [H], [O] and [OH], through R786, R750, R740 and R787. The reaction between FeO and H 2 to produce H 2 O provides an extra channel for consuming H 2 . As a result, the radical concentration in the reaction system could be greatly reduced. In addition, because of its combustibility, Fe(C 5 H 5 ) 2 could compete for O 2 with H 2 during the reaction process. As the O 2 content decreased, this competition effect becomes stronger gradually, which causes better suppression effect for fuel-richer condition. However, the extra heat released by Fe(C 5 H 5 ) 2 +O 2 and CO + [OH] could cause a small increase of the pressure peak for fuel-lean condition. • Fe(C 5 H 5 ) 2 could cause both suppression and enhancement effect on H 2 explosion. • A coupling suppression mechanism of O 2 competing and radical annihilating is revealed. • The extra reaction heat released by Fe(C 5 H 5 ) 2 and oxygen results in pressure rise. • Fe(C 5 H 5 ) 2 and its decomposition substances could directly consume [H] and [O]. • The reaction between FeO and H 2 provides an extra channel for consuming H 2 .