【作者】 李敏贤；

【导师】 戴凌汉；

【作者基本信息】 北京化工大学 ， 机械设计及理论， 2012， 硕士

【摘要】 人类的生存离不开水。对污水的处理和再利用，不仅能减小污水对环境所造成的危害，同时也是解决水资源短缺的重要途径。连续式砂滤器是在水处理方面应用广泛的设备之一，在过滤领域有着重要的地位。本文研究了砂滤器发展的状况和趋势，阐述了连续式砂滤器的工作原理、特点和结构形式，针对目前砂滤器存在的问题，改进了连续式砂滤器的提砂系统和洗砂系统，设计了新型波纹提砂管和螺旋洗砂器。利用CFD软件FLUENT对新型波纹提砂管和螺旋洗砂器的功能进行了数值模拟，并在参数分析的基础上对结构进行了优化。通过对新型波纹提砂管与传统提砂管的对比，发现新型波纹提砂管在保证提砂量的情况下，极大的增强了提砂管内的湍流状况，提高了提砂系统初次洗砂的效果；通过对新型螺旋洗砂器和传统洗砂器的对比，发现新型螺旋洗砂器洗砂路径长，悬浮物等杂质与滤料分离效果好，其在多方面性能上均优于传统洗砂器。此外，本文还对螺旋洗砂器的性能进行了实验测试，验证了数值模拟结果。最后，在充分研究的基础上，完成了NCSF新型连续式砂滤器整体设计，并给出了NCSF连续式外循环砂滤器尺寸系列。更多还原

【Abstract】 Human can not survive without water. By reusing the treated sewage andeffluent, their harmful effects on the environment can be avoided andmeanwhile the shortage of water resource can be solved in some extent.Continuous sand filter plays an important role in the filtration area and widelyused in water treatment fields.In this thesis, the present state and future trend of the sand filter wereanalyzed and the working principles, characteristics and structures of thecontinuous sand filters were introduced. To solve some problems existed in thepresent sand filters，traditional sand lifting system and sand washing systemwere improved by adopting new structures namely corrugated sand-liftingpipe and spiral sand washer. CFD software FLUENT was used to simulate thefunctions of the corrugated sand-lifting pipe and the spiral sand washer. Byperforming parametric analysis, their structures were optimized. Comparingthe corrugated sand-lifting pipe with the traditional sand-lifting pipe indicatesthat if the amount of sand-lifting is the same，the turbulence of fluid and thesand washing effect were greatly enhanced in the corrugated sand-lifting pipe.Similarly, comparing the spiral sand washer with the traditional sand washer, it is found that the sand washing path of the spiral sand washer is longer and theseparation of the sludge and sand is better, or in other words, the spiral sandwasher is superior to the traditional sand washer in many respects. In addition,on the basis of the numerical simulation, experiments for the performance ofthe spiral sand washer were also conducted. Finally in this thesis, the entireNCSF continuous sand filter is designed and the size of the series of NCSFcontinuous outer loop sand filters was given.更多还原