Abstract
To investigate the effects of phase change material-hydrate salt and CO2 on suppressing hydrogen explosions. Experimental methods were used to obtain the pressure and time parameters for hydrogen explosion suppression by Na2CO3 · 10H2O and CO2, and numerical simulations were conducted to clarify the inhibition mechanism. The findings demonstrated that the suppression effect of Na2CO3·10H2O–CO2 on hydrogen explosions strengthened as the CO2 concentration rose. The addition of 10 g of Na2CO3·10H2O showed the most significant suppression effect. Under fuel-rich conditions(φ = 1.4), Na2CO3·10H2O–CO2 exhibits the most effective suppression of hydrogen explosions. Adiabatic flame temperature (AFT) and laminar burning velocity (LBV) of hydrogen‒air mixtures decreased with increasing hydrated salts and CO2,the maximum reductions were 36.1% and 86.5%. H, O, and OH were crucial in the explosion reaction, with H radicals experiencing the most significant reduction, decreasing by 97.16% at φ = 1.4. The reaction: CO + OH ≤>CO₂+ H, and the reaction with sodium-containing radicals: NaO + H + M ≤> NaOH + M, showed the best inhibitory effect. This research offers a theoretical foundation for phase change materials in hydrogen safety and disaster prevention.
•Na2CO3·10H2O crystal water falls off and absorbs heat.•Na2CO3·10H2O and CO2 synergistically suppress hydrogen explosion.•Active free radicals influence the chain reaction process.•Sodium-containing groups and CO2 participate in the chain reaction process.