【作者】 马晶；

【导师】 赵修建；

【作者基本信息】 武汉理工大学 ， 材料学， 2002， 硕士

【摘要】 本文在前人关于数学模拟研究的基础上，建立了耦合玻璃液传热与流动模型、火焰空间模型和配合料熔化模型的浮法玻璃熔窑综合数学模型，并在此基础上建立了化学浓度扩散模型和玻璃液澄清模型。论文采用SIMPLEC算法计算了玻璃液的流场和温度场分布，计算和模拟了不同工作制度时玻璃液中气体浓度分布和气泡澄清过程。 通过对玻璃液中气体浓度场分布计算和气泡澄清过程的模拟研究可知：各种气体在玻璃熔窑前区熔化部位置浓度分布较大，在熔窑后区澄清区和冷却部浓度分布较低；澄清一段时间之后，在熔化部热点附近，玻璃液中残余气泡的尺寸较小，而澄清区和冷却部，玻璃液中残余气泡尺寸相对较大。气泡的澄清过程受玻璃液流场的回流影响较大。 不同温度制度时的玻璃液澄清过程研究表明：桥形和“双热点”温度制度相较于山形温度制度，玻璃液整体温度升高，而热流稳定性不变。“双热点”温度制度时玻璃液中的气泡澄清情况最好。窑内气体总压的变化研究表明：随着窑压降低到15KPa玻璃液中气体浓度分布仅略有降低，只有当窑压为25KPa时玻璃液的澄清情况较好。玻璃液表面张力变化研究表明：当玻璃液表面张力降低时，玻璃液粘度减小，有利于气泡澄清。在澄清前区内，表面张力大(0.38N／m~2)时，气泡的澄清情况好于表面张力小时的情况，而到冷却部之后，表面张力小的玻璃液气泡澄清状况开始变好。出料量变化研究表明：出料量的变化影响澄清指数的大小，即影响澄清条件的好坏。出料量少时，熔窑内玻璃液温度升高，粘度降低，气泡逸出时间减少；出料量少，玻璃液流速降低，玻璃液在熔窑内停留时间增加，玻璃液澄清时间增长，因此玻璃液的澄清指数变大，玻璃液的澄清条件改善。当出料量由多变少，玻璃液中气体浓度显著降低，最终气泡澄清数量提高很多。更多还原

【Abstract】 With a whole consideration of three mathematical models, namely glass flow movement and heat transfer model, which have been established particularly for float glass tank by predecessors, the chemical concentration diffusion model and air bubble fining model are built in thesis. The method of SIMPLEC was applied to calculate the distribution of temperature and velocity field, and subsequently the gas concentration distribution in glass liquor is calculated and the process of bubble fining is calculated under different working conditions.Studying on the distribution of the gas concentration field and the simulation of the bubble fining process, it can be concluded that: gas concentration is a little high in the former of the glass tank, while it is somewhat low in the fining and cooling area of the glass tank; after fining for a time, the air bubbles on the hotspot is smaller, while it is a little big in the fining and cooling area. The fining process of air bubble is influence greatly by the circulations of the glass velocity field.From the research on the different processing systems, the following conclusions can be drawn. Compared with the "Mount" temperature system, the "double hotspot" and the "bridge" temperature system have high temperature and its bubble fining is best. The study on the variation of the gas pressure in the tank shows that: when the pressure reduces from normal degree to ISKpa, the gas concentration has only a little low. When the pressure is at 25KPa, the glass fining is perfect. It is shown by the study on the variation of surface tension that the viscosity of glass decrease when the surface tension went down, which is of help to fine the air bubble. In the front fining area of the tank, the surface tension was relatively high (about 0.38N/m2 ), the glass liquor fines much better than it could do when the surface tension is low, but in the back part of the cooling area, the glass liquor with low surface tension could also fines well. The study on the change of the output capacity shows that it has great influence on the fining exponential, namely good or bad fining conditions. When the output is less, thetemperature in the tank, goes up, the viscosity reduces, accordingly, the time in which bubble comes out of the liquor is shortened. Furthermore when the output is less, the velocity of glass liquor was low and the fining time was relatively long, thus the glass fining exponential is high, correspondingly, the glass fining condition is improved. When the output verified from more to less, the gas concentration in glass is obviously low, and the amount of the fining bubble is increased.更多还原