Experimental Study On The Suppression Of Explosion Flame In Pipelines With Porous Materials

The emergence and rapid development of pipeline transportation technology had a significant impact on the development of the world's energy economy.With the development of the national economy and the substantial improvement of people's living standards,the utilization rate of combustible gas has also been increasing.But the ensuing explosion accidents of combustible gas pipelines are also increasing year by year,causing great harm to people's lives and property.Therefore,the study on suppression and isolation technology of combustible gas explosion in pipelines has a very important significance.In this paper,through the visual explosion pipeline designed all by ourselves,the related characteristics of porous material about combustible gas explosion suppression and isolation were studied,including foam ceramic and foam metal and other materials,the research findings are as follows:(1)The visual explosion experiment system of small-scale and medium-scale has been designed and processed by ourselves,including explosion pipeline,high-speed photography system,ignition system,synchronous external triggering system and pressure data acquisition system.The clamping device were designed and processed.Relevant research on suppression and isolation mechanisms about the porous material placed in pipline can be study.(2)On the basis of small-scale explosion pipelines,the related research on the characteristics of explosion flame isolation technology with foam ceramic was carried out.The effect law of explosion overpressure and flame propagation rate with the PPI and length of foam ceramic and the initial pressure of premixed combustible gas in the pipeline was studied.The experimental results were processed to obtain the curves of explosion flame propagation velocity over time and the curves of explosion overpressure with different PPI and lengths.The analysis showed that the isolation of foam ceramics to low-velocity explosion flame explosion was useful.For high-speed deflagration flame,explosion isolation effect is very limited,and often to promote the deflagration flame further to the detonation flame transition.(3)Through the comparative experiments,the foam metal is far superior to the foam ceramic in impact resistance,and because of the good thermal conductivity and ductility of the foam metal,the explosion isolation characteristic is better than that of the foam ceramic;in the case of the same material,the porous material with a pored ensity of 20 PPI has better performance for explosion isolation.The porous material with a pore density of 10 PPI has a very limited quenching effect,which often promotes the explosion flame.Porous materials with a pore density of 30 PPI can be easily promoted the flow flame to form a local explosion due to the large blockage ratio,which led to failure of explosion isolation.(4)Based on the medium-scale explosion pipeline,the explosion flame suppression technology was researched.Through the arrangement of airgel felt porous material on the pipeline wall,the explosion overpressure and flame propagation velocity are attenuated based on the absorption and destructiveness of the shear wave.The experimental results show that the airgel felt can effectively attenuate over 30% of the explosion overpressure.