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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 flame resistance characteristics of wire mesh and its influence factor on syngas explosion were researched by experiment. Relationships between flame propagation and pressure rise at the flame resistance system two ends were clarified under different flame resistance results. And the effect of syngas concentration on explosion parameters was obtained and flame resistance mechanism was also revealed. Results indicate that the existence of wire mesh could indirectly affect pressure rise by affecting the flame propagation, and flame propagation and pressure rise presented a clear corresponding relationship. The wire mesh could play a better inhibiting role and reduce the explosion intensity, affecting by syngas concentration. As the flame resistance failed (c =30%), △ P max was effectively decreased from 0.81 MPa to 0.52 MPa above wire mesh and from 0.58 MPa to 0.39 MPa below wire mesh. And the reduction extent was more significant under flame resistance success (80.25% and 68.97%). With reduction of syngas concentration and increase of mesh layer, explosion parameters were evidently decreased. Especially the temperature above wire mesh did not present an increase trend and reach the ignition point of syngas under flame resistance success. The inhibition mechanism was mainly attributed to the combination of endothermic and wall effects. [ABSTRACT FROM AUTHOR]

• Relationship between flame propagation and pressure rising was analyzed deeply. • Effect and mechanism of obstacle parameters on explosion intensity were clarified. • Regular of flame "reverse oscillation" was determined and mechanism was discussed. • Effective suggestion was proposed based on the research for practical application. This experimental study focused on effect of obstacle on the syngas (H 2 /CO) explosion characteristics under lean-fuel conditions. The relationship between the flame propagation characteristics and explosion intensity, and effects of syngas concentration, obstacle number and blocking rate on explosion parameters were obtained. Results indicate that the flame propagation and pressure rise were corresponding inside the closed vessel. Obstacle could affect the flame propagation process by changing flame structure, which further indirectly affected the flame velocity and explosion intensity. The "reverse oscillation" flame appeared in the later stage due to the interaction between the flame front and reflected pressure wave, and affected by the obstacle condition and syngas concentration. Meanwhile, the peaks of velocity history were obviously increased, and their appearance moment and the interval time between adjacent peaks were decreased with increasing syngas concentration, obstacle number and blocking rate. Especially the maximum flame propagation velocity (v max) was increased by 88.90%, 60.59% and 61.65%, respectively. The maximum explosion pressure (△ P max) and two peaks of pressure rising rate history also presented an increasing trend. However, the first peak appearance moment had a slight delay due to the blocking effect with the increases of obstacle number and blocking rate in the initial stage of flame propagation. [ABSTRACT FROM AUTHOR]