【作者】 蔡乐；

【导师】 熊德琪；

【作者基本信息】 大连海事大学 ， 环境科学， 2005， 硕士

【摘要】 随着船运液化气运输量的不断增加,液化气船发生泄漏事故造成危害的风险也日益增加。对泄漏液化气在大气中的扩散过程和影响范围进行合理的数值模拟并将其结果准确直观地显示,能够为液化气船泄漏事故应急决策提供有效的辅助工具。因此,利用地理信息系统(GIS)强大的空间数据分析显示功能,进行基于GIS的液化气船泄漏事故大气扩散模拟研究具有重要的理论意义和实际意义。 大气扩散模型是扩散过程和影响范围直观显示的基础。目前,大气扩散模型使用比较多的是高斯模型及其修正模型,但由于其假设条件的限制,使用有很大的局限性。本研究在比较大气扩散模型的基础上,根据液化气体在大气扩散中具有随机性的特点,采用Monte-Carlo方法建立了模拟液化气扩散过程的数值模型,并通过Fortran语言进行数值计算。 本研究以面向对象编程语言Visual Basic为开发工具,以基于MapInfoProfessional地图化技术的控件MapX为GIS开发平台,通过文件传递数据的形式,应用组件技术将上述数值模拟模型与地理信息系统进行了嵌入式紧密集成,初步形成应用系统。实现了GIS支持下的计算网格的自动划分、浓度等值线绘制等功能,以及实现液化气泄漏事故的大气扩散数值计算和模拟结果时空分布的可视化表达,将液化气船泄漏事故的扩散过程和影响范围实时直观地显示在计算机上,达到直观动态的效果,为液化气船泄漏事故应急决策提供有效的辅助工具。更多还原

【Abstract】 With the increasing transportation of liquid gas by gas carriers, the risk of spilled liquid gas by gas carriers are getting higher and higher. So the reasonable atmosphere numerical modeling of spilled liquid gas and the display of the numerical results well and truly could provide assistance to meet an emergency decision-making of the spilled accidents. By taking advantage of the GIS’s capacities of analysis and visual expression on spatial data, the research on atmosphere diffusion simulation of spilled liquid gas based on GIS has important theoretic and practical significance.Atmosphere diffusion simulation model is the foundation of the liquid gas diffused and the resulting display. At present, the Gaussian model and it’s modified models are used to simulate the diffusion in the atmosphere, but they are limited in use with their hypothetical terms. Based on the contrast of atmosphere diffusion models and combination with the liquid gas diffusing in the atmosphere with random trait, the Monte-Carlo method is used to build up atmosphere diffusion simulation of spilled liquid gas and put up numerical simulation by Fortran language.The GIS component (MapX) and an object-oriented programming environment (Visual Basic) are used to integrate the numerical models and GIS as a software system. With the help of the GIS module, the formation of calculation grid and isoclines, and other functions can be approved. The results of the atmosphere diffusion simulation of liquid gas of gas carriers could be dynamically and visually expressed on the computer screen. The system helps to enhance the efficiency of meeting a spilled emergency decision-making.更多还原