Hydrogen leakage and explosion under the influence of water mist in a marine engine room

To investigate the water mist suppression mechanism of hydrogen leakage, diffusion, and explosion, a fire explosion model under the influence of multiple water mist parameters is constructed, and parameter sensitivity and combined effect analyses are performed. The results indicate that hydrogen can quickly accumulate after leakage and diffusion, and generate high-intensity, high-temperature, and high-pressure explosive loads after ignition. Properly deploying water mist can reduce the hazardous area by 9.5 % compared to the without water mist, conversely, it will increase by 23.1 %. During the explosion stage, water mist can reduce the peak overpressure by 6.9 % and the pressure rise rate by 19.4 %. When the flow coefficient is 0.7, the hazardous area decreases by 24.1 %, but if the coefficient is too high, it will weaken the explosion suppression effect. Increasing the water mist operating pressure can reduce the hazardous area to 165.4 m 3 . Overall, the location of water mist is a relatively critical single factor, while the flow coefficient and operating pressure exhibit a high combined effect. Multi-parameter collaborative matching is required to achieve full process risk control, and research can provide a theoretical basis for the design of confined space water mist explosion suppression systems.