【作者】 袁红燕；

【导师】 王伟文；

【作者基本信息】 青岛科技大学 ， 化学工程， 2007， 硕士

【摘要】 本研究以流体模拟软件Fluent6.2模拟α型水力旋流器流场结构及固体颗粒运动情况，分析了旋流器内的涡流状况和固体颗粒的运动轨迹，为改善旋流器内流场分布，提高旋流器的性能提供理论依据；并在模拟结果的指导下，提出采用锥形渐扩溢流管结构以降低能耗、提高分离效率。所作主要研究工作如下：1、运用流体模拟软件Fluent6.2，基于RSM模型对旋流器模型进行模拟运算，结果表明：α型旋流器消除了常规旋流器存在的“砂环”的影响；流型规整、流场稳定，减少了入口部位阻力损失。分离空间内切向速度和轴向速度分布的轴对称性较好，旋流腔不存在次级涡流。2、在RSM模型模拟湍流流场的基础上，采用相间耦合的随机轨道模型对固体颗粒运动轨迹进行初步考察，并对不同粒径颗粒的分离效率进行了模拟与实验的比较分析。结果表明，进入旋流器的大颗粒旋转的螺距较大，颗粒被迅速甩向器壁旋转向下，进入底流被捕集。小颗粒旋转的螺距较小，它离开(被捕集或逃逸)分离器的时间(路程)较长。该方法对于粒级分离效率具有一定的预测性。3、提出采用锥形渐扩溢流管结构的旋流器，模拟结果显示：溢流管结构的变化基本上未改变压力的分布：在溢流管内，只有动压分布受到影响；而在分离空间内，其各项压力分布与普通旋流器内的分布趋势基本相同。溢流管内的切向速度值低于常规型，而其他有效分离空间内的切向速度值均高于常规型。4、α型旋流器实验测试结果表明：对于高固含量的物料(固体质量分数高达60％)，渐扩溢流管的α型旋流器的分离效率达到了92％以上，其性能提高显著。更多还原

【Abstract】 In this work, the theoretical study of turbulent filed simulation ofα-typehydrocyclone was carried out with FLUENT6.2 CFD software. The vortex in theseparator, the moving behavior of the particles, as well as the factor which influencethe separation efficiency were analyzed in order to improve the performance of theα-type hydrocyclone. On the base of simulation, the researcher put forward usingextend overflow tube to improve the performance of theα-type hydrocyclone. Theworks are as following:1.The method of FLUENT6.2 and RSM model were selected to simulate theα-type hydrocyclone and the results showed that: It eliminated the influence of"sandannulus"; the flow filed was more steady and the energy loss was more decreased.2.On the base of RSM model simulation, the moving behavior of the particles wasstudied with the stochastic model of interaction with continuous phase elementarily,and the simulation results were compared with the experiments. It showed that theresult of experiment can forecast the efficiency of different size of particles.3.The solution was put forward to use extend overflow tube for betterperformance. Simulation results showed that: the structure change of overflow tubedidn’t change the distribution of pressure. In the overflow tube, it just had an influenceon the dynamic pressure; in the separate space, the distribution trend of pressure wasthe same with traditional hydrocyclone. The tangential velocity in the overflow tubedeclined compared with the traditional hydrocyclone, but in other available separatespace, the tangential velocity ascend. It illuminated that: The centrifugal force wasenhanced which can improve the separation efficiency.4.The configuration optimized overflow tube was thus designed and added to theexperimental setup and the results of the experiment proved that this extend overflowtube can improve the performance ofα-type hydrocyclone successfully.更多还原