Theoretical Study Of An Intelligent Real-Time Forecast In Diffusion Process Of Main Risk Source (Liquid Hydrocarbon) With Numerical Simulation

According to the statistics of accident frequency on major risk sources all over the world, the sources that are mainly composed of hydrocarbons and related equipments are amounted to more than fifty percent on the whole disastrous. Thence, it, so far, has been important project for people to realize real-time monitor and dynamic simulation in accidental diffusion of hydrocarbons. As main components of national 95' research project, the dissertation, here, gives a deep study on mechanism and process mathematical models of hydrocarbon on dispersion process. At the same time, the characteristic of main factors that master dispersion of hazardous materials is analyzed systematically. And then, a new method of dynamic forecast has been proposed, and the system of intelligent forecast dynamic simulation (IFDS) is established.Firstly, the dissertation gives a general review on current situations of dynamic modeling and real-time forecast in accidental diffusion of major risk sources. According to the characteristics of opening and variation on atmosphere environment, the mathematical models, which describe the process characteristics of thermodynamics, fluid dynamics and atmosphere physics are presented. The characterization of source, liquid flash, spatial concentration of cloud, entrainment and evaporation of liquid hydrocarbon, entrainment of air, phase change and temperature of vapor components, change of volume and radius are discussed.In the dissertation, the double-virtual source models are established, based on the research on models and characteristics of hydrocarbon in heavy gas phase. According to the dilution process of vapor cloud toward vertical axis, the ideas of improving the gauss model is offered here, which gives the slump description and feature constant of dense cloud, down and wind.Because of the quantity loss of virtual point source simulation, the modes of integral small volume source, pseudo volume source model and model iterating are set up. So that accuracy and reality of numerical solution are promoted.Based on the research of related mastering factors, the models , which is used for adaptive adjustments of the value of atmospheric stability (SP) and dispersion parameters (σ ), are presented, and atmospheric condition and ground surface...