Research On Explosion Hazard Of Leaking Gas Cloud Of Natural Gas Pipeline

With extensive use of the high-pressure long-distance gas pipeline, the pipeline leakage explosion accident occurred from time to time. When this explosion accident occurred , it will make great damage to the surroundings, leading to huge losses both in property and persons. Therefore, it is necessary to carry out the research on the explosion behavior of the leaking natural gas clouds and its damage scope in order to provide evidences to take measures to control and lessen the damage.Reasonable models are employed to research on the explosion of natural gas in this paper, the work mainly includes:(1) Numerical models on the steady leakage and the unsteady leakage for natural gas are established using simulation software under some assumptions. From the models, the pipe arrangement can be expressed intuitively and the problem how to choose the leakage model and how to calculate the leakage process are solved in a simple way.(2) The formula to calculate the leakage diameter after the pipe begins to leak is deduced.(3) Based on the aerodynamics and explosion mechanism, energy averaged adding method and artificial viscosity method are established to capture the shock wave in a free domain. Further more, the formula to calculate shock wave under the constrained condition is deduced according to the reflection principle. Upon the abovementioned foundations, the damage scope is evaluated depending on a reasonable destruction guideline and relevant parameters on the effect of the damage scope are analyzed.(4) Formulas to calculate the distance of heat radiation induced by the explosion fireball and the damage radius of the jet flame under the winding condition are established. Eventually, initial parameters on the effect of the explosion fireball and jet flame are analyzed. (5) The abovementioned calculation method is validated through an engineering example.(6) Procedure named EHAS(Explosion Hazards Analysis System)is coded.