Study On Hazard Scope And Movement Rules For Gas Migration And Backward Flow After Gas Outburst

This dissertation arrives at multiple laws of gas migration and backward flowafter gas outburst and hazard scope by applying such research methods as theoreticalanalysis, model experiment and numerical analysis. It analyzes the features of gasoutburst and based on the similar experiment principle of flow in flow field, itestablishes a system of the experiment of gas outburst migration and backward flow.It conducts a quantitative experiment of gas outburst migration in straight roadwayand backward flow in intersection roadway. It also makes an analysis of the influentialfactors of principles of the spatial and temporal distribution of gas concentration. Inaddition, this dissertation derives a mathematical model of the diffusion and migrationof gas outburst turbulence by modification. It proves that the law conforms toattenuation of the concentration of gas migration accorded with negative exponentialfunction and the process of gas backward flow in intersection roadway contains―backward-regressive‖airflow, and represents the feature of double peak. It furthermakes a quantitative demarcation of the dangerous areas of the roadway after gasoutburst in light of the modified model and calculates the backward airflow areas. Italso uses Fluent to simulate the process of backward flow after gas outburst, showingthat the readings fit in with the results of the test. Finally, this dissertation makes aquantitative analysis of the law of gas migration and diffusion in the driving faceunderground, verifying the serviceability of the model. It is hoped that these researchfindings will render firm support to emergency response to accidents, prevention ofsecondary disasters, and emergency rescue.