Diffusion Law Of Ammonia Leakage In Finite Space

Ammonia is a widely used important inorganic chemical product.It could lead to many kinds of damages such as personnel poisoning,burning explosion,environmental pollution and secondary accidents when the ammonia leaks.This thesis studied the leakage and diffusion process of ammonia within limited space according to the hidden dangers of the transportation pipeline leakage in industries which include chemical process and frozen storage,and the investigation used with numerical simulation and experimentation.An experimental platform of ammonia leakage diffusion has been built based on the working conditions of the ammonia transmission pipeline.And the experiment of the leakage and diffusion of ammonia has done.The calculation model of ammonia leakage diffusion in a finite space was established by Gambit and Fluent to carried out the numerical calculation and simulate the diffusion process of ammonia pipeline leakage under the influence of leakage pressure,direction,aperture and position.The thesis explored the concentration distribution and diffusion law of ammonia under different leakage conditions and the relationship between the distance from the point to the source of leakage and the change rate of the ammonia concentration within a certain angle and direction of leakage.The relationship provided a basis for reasonable disposing the Ammonia detector in the design of warning system.Based on the study of ammonia diffusion process in finite space,main research results are summarized as follows:(1)In the finite space,ammonia leakage direction and leakage position are the major factors for ammonia distribution;(2)In the vertical direction of ammonia leakage,leakage pressure and leakage aperture have a significant impact on concentration gradient;(3)In the process of leakage and diffusion,variation of ammonia concentration has three stages of linear increase,fluctuation and steady increase;(4)On the certain condition of leakage and within a specific range of leakage direction,it obtained the relationship between the distance from the point to the source and the change rate of ammonia concentration and the formula,and a basic method for determining the source location quickly was provided.This thesis has studied the small hole leakage on the pipeline in finite space by the experimental research and the numerical simulation,provided the safety emergency measures based on the research results.In the future research,it should strengthen experimental study on the leakage and diffusion of heavy gas and liquid to perfect the study of the general rule of indoor pipeline leakage and diffusion.