Experimental Study On Propagation Characteristics Of Methane Explosion With Different Concentrations In Tubular Space

By means of experimental research,this paper makes an in-depth study on the propagation law of methane explosion in tubular space under different methane concentrations,number of thin film obstacles and concentration gradients,providing important mechanism analysis and technical support for the prevention of methane explosion accidents and emergency rescue.On the basis of theoretical analysis and experimental analysis of the propagation process of methane explosion,the experimental scheme was developed,reasonable experimental conditions were designed,pressure flame sensors were arranged,the experimental steps were introduced in detail,and the pipeline connection system diagram of blasting shock tube was drawn.With flame propagation speed and the change of explosion pressure peak value as the research object,the characteristic parameters such as pipe explosion experiment platform,the use of north China institute of science and technology in different concentrations of airtight pipe methane explosion propagation has carried on the experimental study,analyses the methane concentration,number of membrane barrier and different concentration gradient on the propagation of methane explosion flame propagation speed and the effect of explosion pressure peak.The results of this study are helpful to the analysis of the gas explosion propagation process,the prevention of gas explosion accidents and the analysis of the consequences.The conclusion is as follows:(1)compared with the condition of uniform concentration,the flame propagation velocity and pressure peak in the methane explosion propagation process with concentration gradient distribution are doubled,and the flexible barrier has a strong excitation effect.Under the condition of the same concentration gradient,different number of obstacles have positive excitation effect on methane explosion pressure.(2)in the presence of a single flexible barrier,when the concentration gradient is lower than the lower limit of methane explosion,methane explosion pressure will reach the pressure peak before other concentration gradients.Only when the concentration of methane is above 5% of the lower limit of the explosion can a strong excitation effect be generated.(3)in the experimental study on methane explosion propagation characteristics under the coupling condition of all-block probability thin film and concentration gradient,the explosion overpressure value was relatively too large to set up an optical window for observation.In the next research,this will be improved and further studied.(4)different from rigid obstacles,flexible obstacles will increase turbulence after being broken.The maximum pressure peak is not near the obstacles but behind the pipeline,which can provide certain basis for investigation of partial methane explosion accidents.This thesis contains 42 figures,7 tables and 57 references.