Research Of The Influence Of CO,H₂ On Explosive Characteristics Of Methane Under Abnormal Temperature

The process of gas explosion is affected by many factors,such as gas composition and gas volume fraction,initial temperature,ignition energy,initial pressure and so on.In this paper,the effects of CO and H2 on the explosion characteristics of CH4 were studied at different temperatures,different concentrations and different concentrations of methane under the condition of different temperature,different concentrations and different concentrations of methane.Research has shown that with the increase of initial temperature,the maximum explosion pressure of gas mixture are a nonlinear downward trend,and in the early stage of temperature rise the decrease is the largest and then becomes smaller;The maximum rate of pressure rise increases,and the time to reach the maximum explosion pressure is shortened.Methane in the state of enrichment oxygen,at the same initial temperature,with increasing of the carbon monoxide,hydrogen ' volume fraction,the maximum explosion pressure increases,and the amplitude increases gradually.The maximum rate of pressure rise shows an increasing trend,and the time to reach the maximum explosion pressure decreases gradually.When the volume fraction is less than 2%,carbon monoxide and hydrogen gas can promote the methane explosion in 7%and 9.5%;Methane in the state of lean oxygen,at the same initial temperature,with increasing of the carbon monoxide,hydrogen ' volume fraction,he maximum explosion pressure decreases,and the time to reach the maximum explosion pressure more longer.That is,within the 2%volume fraction,the addition of hydrogen and carbon monoxide will weaken the methane explosion.Add the same volume fraction of hydrogen or carbon monoxide,the maximum explosion pressure of hydrogen-methane are slightly larger than carbon monoxide-methane's,same the maximum rate of pressure rise.The time to reach maximum explosion pressure of hydrogen-methane are shorter than carbon monoxide-methane.The results show that the effect of hydrogen on methane explosion is greater than that of carbon monoxide;The maximum explosion pressure calculated by physical chemistry method is approximately the same as the same time,there is a certain deviation.Uunder the influence of experimental conditions,the experimental value is less than the theoretical value.With the increase of initial temperature,flame propagation speed is obviously increased;Adding hydrogen and carbon monoxide also promoted the flame propagation speed,the effect of hydrogen on the flame propagation velocity is greater than that of carbon monoxide.At the moment of explosion,the velocity of flame propagation in vertical direction is larger than that in horizontal direction,and the flame propagation velocity tends to be consistent with the propagation of flame.