| When a hazardous gas leak occurs in a chemical process,simulation modeling of the dispersion of the hazardous gas after the leak is a key direction of research.We hope to obtain the dispersion concentration distribution of hazardous gases as soon as possible,so that we can delineate the danger zone of the accident and evacuate the people in the danger zone in time to protect their lives and health.The computational fluid dynamics software Fluent,with its powerful model simulation capability,is widely used in the study of gas diffusion and other related problems,and can simulate the gas diffusion process more accurately,but due to its large computational volume,complex model,and long computation time,it cannot meet the requirements of timely acquisition of gas concentration-related data.This research is based on a set of chemical hazardous process simulation training system independently developed by Beijing University of Chemical Technology.Matlab software is used to obtain the results by selecting a suitable gas diffusion model for numerical simulation and analysis.Taking the ammonia leakage dispersion in ammonia process as an example,the feasibility of the Matlab-based gas dispersion simulation model in the classification of hazardous gas concentration areas is investigated.The results show that the proposed method is feasible,and the analysis results are close to those of Fluent software in dividing the hazardous area,and the calculation speed is much faster than that of Fluent,which can better meet the systemrelated functional requirements.In order to further improve the computational accuracy of Matlab model,a method of combining the improved Gaussian plume model and SLAB model is proposed,firstly,several important parameters of the Gaussian plume model are optimized,and then the improved Gaussian plume model and SLAB model are simulated separately using Matlab software and compared with the simulation results of Fluent.The results show that the binding energy of the two models can better improve the overall calculation accuracy,and the average error rate of hazardous area division is 9.1% lower than that of the previous model.The improvement effect is good.The modified model obtained simulates a more accurate impact range of leakage accidents,making the model have higher accuracy and better practical value. |
