【作者】 杨波；

【导师】 许友谊；

【作者基本信息】 江苏大学 ， 流体机械及工程， 2007， 硕士

【摘要】 冲击式食物破碎机具有结构简单、操作快捷方便、维修容易等特点,是一种具有环保作用的废弃食物处理机,因此它的应用前景很广阔。由于引进时间短,国内从事研究的人员主要还是从机械方面对破碎机理进行研究,内部固液两相流的流场研究还没见过相应的报道,特别是粉碎室的特性参数对粉碎室内流场、湍动能和能耗等的影响。本文从湿法粉碎方面去研究破碎机的工作原理,为探究粉碎室内固液两相流流动,也为针对国内饮食习惯为粉碎室进行优化设计打下基础。本文在前人研究的基础上,自行改装冲击式破碎机一台,对其内部液相流场进行了数值模拟计算及实验研究。进行的主要工作及取得的成果如下:1.总结回顾了国内外冲击式食物破碎机的发展过程及已取得的主要研究成果,在此基础上设计并改装了满足测试要求的破碎机模型;2.运用Pro/E软件对设计的模型进行三维造型;并对粉碎室内部流道区域进行非结构化网格划分;3.采用Euler多相流模型及修正的k-ε湍流模型对不同转速下的粉碎室内部液固两相湍流场进行了数值模拟;对轴截面及其他截面进行结果显示,得出“破碎效果随转速增加而改善”等结论。4.介绍了相位多普勒粒子测量技术(PDPA)对旋转机械内流测试的方法;5.构造了实验装置系统,利用丹麦Dantec公司生产的三维相位多普勒粒子测速仪对粉碎室内部液相流场进行测量。6.简要分析了液固两相在粉碎室的轴向、圆周切向及脉动速度的分布规律,提出了“0.6R以外为粉碎有效区”等观点。更多还原

【Abstract】 Impact food crusher has been being the focus on the chamber research for its simple construction, easy maintenance and repair, and environmental protection .So it has an extremely wide application prospect. Since its introduction time is short, domestic researchers have taken research on broken mechanism from the aspect of machinery mainly, but few research on flow filed has been reported, particularly the effect of the characteristic parameter of the crush room on turbulent kinetic energy and energy consumption etc.This paper is researched on the Working principle from the wet grinding method .In order to make foundations of the study on the theory of liquid-solid two-phase flow in the crush room and optimizing design aiming at domestic diet habit. The author retrofitted impact crusher on the basis of other scholars’ study ,and do numerical simulation and experimental research to the internal liquid-solid two-phase flow fields .The main works and conclusions are showed as following:1. Present research states of Impact food crusher and liquid-solid two-phase flow were introduced simply. A model crusher, which met the measurement needs was designed and manufactured based on the methods.2. Pro/E was applied to sculpt the model crusher. The unstructured grids were generated in the area of flow passage in the crusher.3. Euler multiphase flow model and modified k-εturbulent model were adopted to simulate internal liquid-solid two-phase flow field at different rotate speed of crusher. Axial cross-sections and regions were plotted to locate every measure point and display the results for comparing with the measurement results. Conclusions were obtained such as that "broken effect has improved with the increasing rotation rate".4. Measuring means on internal flow of rotating machines with Phase Doppler Particle Analyzer (PDPA) were introduced.5. Experimental set were designed. The internal liquid flow field in model crusher was measured by PDPA made by Dantec in Danmark.6. Circumferential, axial velocities and relative fluctuate velocities were analyzed. Conclusions were proposed such as "outside 0.6R, which is the main crush area" .更多还原