Laboratory Research On Diffusion Law Of Gas Leakage Accidents In Chemical Industry

A comprehensive experimental platform for oil-gas storage and transportation safety was constructed in Jiangsu polytechnic university based on similarity theory.Qualitative and quantitative experiments were respectively carried out using tracer technique according to the different purposes of experiment and released location. Colorful smog combined with digital photography was employed in qualitative method, which could study the flow diffusion modes and forms of leakage. Carbon dioxide associated with on-line detection system was utilized in quantitative method, which could detect the concentration distribution in the process of diffusion.Fluent, one of the softwares of computer fluid dynamics was used to carry out the geometric model building and the mesh division. Then, boundary conditions were set combined with experiment conditions. The velocity diagrams, vector diagrams as well as concentration diagrams were obtained after analog approach, which visually and intuitionistically expressed the law of diffusion after leakage.Proper mathematical models were picked up to analyze the results of the experiment in different points and aspects. Multiple regression analysis was employed to quantitatively judge the similarity of the model, which indicated that the experimental model built in laboratory, could well reflect the real conditions, emulation degree of the model was high, and the fitting effect of the data was perfect; The results of experiment was generalized connect with data in experiment based on similarity theory and obtained the most valuable achievement: mathematical expression of the diffusion laws of harmful gas, further, the expression was certificated and the results showed that the error of the expression was small and the expression could be generalized in laboratory; Principal Component Analysis was used to analyze the major and the minor influencing factors and influencing coefficients were quantified, then, the three mathematical models were obtained which could be reduced to distance factors, velocity factors and the natural factors; Trend-Season model was employed to predict the diffusion trend of the gas, The research has a certain reference value to the prediction of trend , the construction of emergency response rescue plan and the implementation of effective field control.Finally, it was carried out the contrastive analysis to the results of the experiment and the simulation, and simply analyzed the reasons of the error in terms of the model building, simulation solution and the experiment.