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Synergy inhibition of wire mesh and spray mist on syngas explosion was researched. The correspondence between the explosion parameters under success and failure conditions were analyzed, and its influence regular and inhibition mechanism were revealed. An evident difference appeared in the correspondence at different synergy results. Compared with the failure, the pressure of lower end only experienced an acceleration rise under the success condition although the propagation velocity of flame was slightly increased as it approached wire mesh. Corresponding pressure was also reduced. After passing through wire mesh, flame propagation was evidently accelerated due to the turbulence disturbance caused by wire mesh despite the strong endothermic effect of mist. The corresponding explosion reaction rate was also increased. Pressures of two ends did not appear obvious change under the success condition, but the pressure of upper end was evidently reduced compared with the failure. Due to the combined effect of wire mesh disturbance and mist heat absorption, the velocity history showed a change of increasing firstly and then decreasing as the spray time increased after passing through wire mesh. The synergy inhibition was attributed to the combined physical and chemical effects, and was related to the syngas concentration and spray amount. [Display omitted] • Synergy effect of resistance/inhibition on protection of gas explosion was studied. • Correspondence between explosion parameter during success and failure was clarified. • Effects of mist amount and syngas concentration on explosion parameter were grasped. • Critical value of synergy effect for complete inhibition of explosion was proposed. • Effective engineering guidance was proposed and its synergy mechanism was revealed. [ABSTRACT FROM AUTHOR]

• The temperature of H 2 jet flame with suppressants addition are analyzed. • Water mist containing DMMP exhibit good suppression effect on H 2 jet flame. • The influence of DMMP on lean CH 4 and lean H 2 flames is compared. • There is no combustion enhancement effect of DMMP on lean H 2 flame. This work investigates the suppression effect of water mist containing dimethyl methylphosphonate (DMMP) on H 2 jet flame. The flame appearances are analyzed and the flame temperature is recorded by a high-speed infrared camera. Results show that the suppression effect of water mist containing DMMP is better than that of pure water mist. To better understand the suppression effect of water mist containing DMMP, the burning velocity, heat production and free radicals are analyzed. Results indicate that suppressant could scavenge lots of free radicals to reduce the burning velocity in a wide range of equivalence ratios. Moreover, the influence of DMMP on lean CH 4 and H 2 flames is compared. Different with that of lean CH 4 flame, the combustion parameters of lean H 2 flame decline with DMMP addition. There is no combustion enhancement effect of DMMP on lean H 2 flame. Because of the higher combustion intensity of lean H 2 flame, the hydrocarbon in DMMP has little impact on the combustion. Furthermore, the reaction path of DMMP decomposition is analyzed. Results demonstrate that the rates of most phosphorus reactions in H 2 flame are larger than that in CH 4 flame. This work could provide foundation for improving the safety of hydrogen energy application. [ABSTRACT FROM AUTHOR]

• Numerical model of methane explosion inhibition by the water mist was established. • Calculation result was validated by experiment through pressure and flame changes. • Heat transfer between water mist and explosion flame was analyzed quantitatively. • Vapor pressure as a component of explosion pressure in a closed vessel was studied. • Effects of mist parameter on heat transfer process and vapor pressure were studied. This numerical study focused on the heat transfer process between the ultrafine water mist and explosion flame, and the suppression mechanism of ultrafine water mist and the effect of mist parameter on methane explosion. Hence, a three-dimensional numerical model for methane explosion suppression by ultrafine water mist was established. Large eddy simulation and partially premixed combustion models were used to determine the explosion flow field characteristics and methane explosion process, respectively. The Euler-Lagrange equation was used to solve the continuous and discrete phases, and the coupling calculation was realized by alternately solving these two phase models. In addition, the validity of the numerical model and calculation method was verified by the experimental results. Mist vaporization, heat transfer between the gas and liquid phases, and influencing factors (including the mist diameter (d), mist velocity (v), and mist concentration (Q Mist)) were analyzed quantitatively. The results indicate that heat exchange mainly occurs in the reaction zone, and the heat exchange rate can be affected by the mist parameters, which further affects the temperature inside the vessel. Moreover, the vapor pressure generated from mist vaporization is an important component of the explosion pressure in the closed vessel, and it is comprehensively affected by the mist vaporization rate and temperature. Simultaneously, the mist parameters are also the key influencing factors for the above process. [ABSTRACT FROM AUTHOR]