气液两相流喷嘴的射流雾化机理的研究

发布时间：2018-11-25 17:09

【摘要】：我国的大气污染日益严重,而包含大量二氧化硫和氮氧化物的火电厂煤烟是首要的污染来源。随着环保法规的日益严格,国家强制燃煤电厂进行烟气脱硫并安装脱硝装置。脱硫脱硝过程中,通常会使用喷嘴,而气液两相流喷嘴以其优越的性能得到了广泛的应用。本文便以气液两相流喷嘴为研究对象,通过理论分析、数值模拟和实验研究三种方法,对其射流雾化机理进行了研究,并应用于实际工程。理论分析方面,主要介绍了气液两相流喷嘴的雾化机理,建立了数学模型的控制方程、湍流模型和组分输运模型。对控制方程进行离散并通过交错网格和SIMPLE算法对离散方程进行求解。数值模拟方面,简单说明了CFD软件及其应用,详细描述了气液两相流喷嘴几何模型的建立和网格化分,确定初始条件和边界条件,并对相关参数进行设置。对两相流喷嘴的内外部流场进行了数值模拟,得出了喷嘴结构参数和工作参数对液滴粒径尺寸分布的影响。实验研究方面,介绍了气液两相流喷嘴的实验台、实验用两相流喷嘴和实验测量坐标系。通过对多次实验结果进行分析和总结,得出了喷嘴内部的供液管、控气块和导气块对雾化效果的影响。以上述所做的研究工作为指导,将气液两相流喷嘴应用到实际工程中,与其它工业设备和控制系统相结合,既满足了工艺要求,又大大节约了水的消耗量。从而为企业节省了成本,具有较强的现实意义。最后,对气液两相流喷嘴射流雾化机理的研究进行了总结,所得结论为以后气液两相流喷嘴的研究提供了参考,并对如何改进研究的不足之处进行了展望,希望今后的研究能对其进行补充和完善。
[Abstract]:Air pollution is becoming more and more serious in China, and soot is the primary source of pollution in thermal power plants, which contain a large amount of sulfur dioxide and nitrogen oxides. With the increasingly strict environmental protection regulations, the national forced coal-fired power plant flue gas desulphurization and installation of denitrification device. In the process of desulfurization and denitrification, nozzles are usually used, while gas-liquid two-phase flow nozzles are widely used for their superior performance. In this paper, the atomization mechanism of gas-liquid two-phase flow nozzles is studied by means of theoretical analysis, numerical simulation and experimental study, and applied to practical engineering. In terms of theoretical analysis, the atomization mechanism of gas-liquid two-phase flow nozzles is introduced, and the governing equations, turbulence models and component transport models of the mathematical model are established. The governing equations are discretized and solved by staggered grid and SIMPLE algorithm. In the aspect of numerical simulation, the CFD software and its application are briefly explained, the geometric model of gas-liquid two-phase flow nozzle is described in detail, the initial conditions and boundary conditions are determined, and the relevant parameters are set up. The internal and external flow field of the two-phase flow nozzle is numerically simulated, and the influence of nozzle structure parameters and working parameters on the size distribution of droplet is obtained. In the aspect of experimental research, the experimental bench of gas-liquid two-phase flow nozzle is introduced, the two-phase flow nozzle and the experimental measuring coordinate system are used in the experiment. Based on the analysis and summary of many experimental results, the influence of liquid supply pipe, gas control block and gas guide block inside the nozzle on the atomization effect is obtained. Under the guidance of the above research work, the gas-liquid two-phase flow nozzle is applied to practical engineering, which is combined with other industrial equipment and control system, which not only meets the process requirements, but also saves the water consumption greatly. Thus saving the cost for the enterprise, has a strong practical significance. Finally, the research on atomization mechanism of gas-liquid two-phase jet nozzle is summarized, which provides a reference for the later research of gas-liquid two-phase flow nozzle, and prospects how to improve the research deficiency. It is hoped that the future research can complement and perfect it.
【学位授予单位】：山东建筑大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：X773

【共引文献】