Research on Experiment and Numerical Simulation of Fuel-Air Explosion and Explosion Suppression in Confined Spaces

The explosion combustion model of fractional reaction control mechanism is established based on the previous experimental results, the regularity and mechanism of the fuel-air explosion and explosion suppression in confined spaces and the characteristics of explosion combustion and explosion suppression. The impacts of fuel-air explosion and explosion suppression by different control mechanisms can be simulated by it to describe the interaction between the pressure wave and the flame in the process of explosion and explosion suppression. The difficulties in calculation of reaction and flow coupling and storage can be overcome for easier numerical solution by the model. The results show that the flame is deforming in the process of propagation because of the effects of turbulence and flow. It accelerates in a fluctuations scope, not accelerating all the time. The maximum value can reach 111 m/s. The inner of the initial fireball will form a preheating region with temperature gradient around it after a certain period of chemical reaction to preheat the unburned mixture behind in order to speed up the flame propagation. When the explosion suppressant is used, the suppressant cloud restrains the propagation of the flame and explosion pressure because of the strong restraining effect of the explosion suppressants and the energy and momentum exchange between the fuel-air and particle phase. The pressure wave is weakened because there is no energy added that is provided by fuel-air combustion. And the explosion dissemination is suppressed quickly. The bigger its ejecting dosage and velocity are, the more easily explosion can be suppressed. It is easier to suppress the explosion at the initial stage by the weak coupling effect between the flame and the pressure wave. The regularity of related parameters in the process of fuel-air explosion and explosion suppression in confined spaces is revealed. And the mechanism of explosion suppression is analyzed. The theory reference and key design parameters are provided for the development of the subsequent device for explosion suppression,