Study On Leakage And Diffusion Of Odorous Gas Based On FLUENT

With the rapid development of society,the demand for energy is increasing,which leads to a mass use of fossil energy,and the main source of energy is fossil energy.Natural gas is the most clean source of fossil energy,so it accounts for a growing proportion of energy use.However,the ignition point of natural gas is low,and a little spark will ignite the gas fire after leakage,causing inestimable loss.At present,in addition to the professional instrument that can detect nature gas leaks,most residents can only rely on the smell of odorants in natural gas to detect their leaks.When the amount of odour added in natural gas is too low,people will not be able to detect the leakage after the leaks.Therefore,the addition of natural gas odorant is particularly important to ensure the safety of residents.In this paper,the natural gas odorant and its influencing factors are studied at first.It is found that the temperature has a great influence on the content of the odorant in the initial adding pipeline,and the different adding ways also affect the concentration of the odorant in the pipeline.Under the dual influence of temperature and adding mode,the difference of odorant concentration in the pipeline will reach more than 3 times.In summer,the temperature is higher,the molecular diffusion is faster,and the sensitivity of nose at high temperature is higher than that at low temperature.Therefore,the amount of odour can be reduced properly when adding deodorant in summer.The discovery of natural gas leaks does not mean that accidents can be avoided.It need further studying the law of natural gas leakage and diffusion,and taking correct measures can the accident be avoided effectively.Therefore,in this paper,the law of natural gas leakage and diffusion is further studied,based on the jet theory,the leakage and diffusion model of natural gas pipeline is established,and the numerical simulation calculation is carried out by using FLUENT software.The effects of different temperature,different leakage caliber,different leakage rate,different wind speed and different height of obstacles on the diffusion of natural gas containing odorant are simulated.It is found that at the same leakage rate,the greater the difference between the temperature and room temperature of natural gas in the pipeline,the more downward the natural gas accumulates after leakage,which leads to a great concentration ofnatural gas in the lower part of the pipeline,which makes it easy to occur dangerous accidents.The leakage aperture in 20 mm is larger than that in 10 mm,but the leakage trend is basically the same.When the leakage caliber is constant,the leakage range of methane with large leakage rate is larger than that of methane with small leakage rate,and the indoor accumulation concentration of methane with large leakage rate at the same leakage time is larger than that of methane with small leakage rate.When there is no wind,the gas mainly diffuses upward after leakage.With the increase of wind speed and the action of wind pressure,the larger the wind speed is,the smaller the concentration of natural gas near the leakage outlet is.Pay attention to ventilation when using natural gas for safety.When there are obstacles,it will change the state of airflow movement,which mainly acts as a hindrance.The concentration of leakage mouth near one side of the obstacle is very large,and the concentration of the back side of the obstacle is very small.With the increase of the height of the obstacle,the gas barrier will also increase.Resulting in an increase in the concentration of natural gas.