细长颗粒与流场双向耦合的气固两相流数值模拟研究

发布时间：2018-01-01 02:01

本文关键词：细长颗粒与流场双向耦合的气固两相流数值模拟研究　出处：《中国电机工程学报》2016年21期 　论文类型：期刊论文

【摘要】：细长颗粒气固两相流中湍流流变特性研究是细长颗粒气固两相流研究的重要内容之一。基于离散单元法、刚体动力学,并引入拉格朗日时间尺度与?-ε模型的耦合关联式,构建起细长颗粒?湍流场气固双向耦合模型,并采用此模型对某一实际流化床内的细长颗粒气-固两相流场进行了数值研究。研究发现,多数细长颗粒以其轴与流场主流速度方向近于平行的姿态在流场中向上运动;在高度上,一方面细长颗粒在此存在会导致此高度上湍流速度梯度的增加从而导致整个高度上湍动能值的增加,另一方面细长颗粒的存在又会消耗一部分当地湍流场的湍动能;水平方向上有细长颗粒存在的区域,当地湍动能值会有明显的下降;细长颗粒的存在会导致整个湍流场的压强梯度增加。
[Abstract]:The study of turbulent rheology in slender gas-solid two-phase flow is one of the important contents in the study of gas-solid two-phase flow with slender particles. Based on discrete element method, rigid body dynamics, Lagrange time scale and Lagrange time scale are introduced. The coupling correlation of-蔚 model to construct slender particles? The gas-solid bidirectional coupling model of turbulent field is used to study the gas-solid two-phase flow field of slender particles in a practical fluidized bed. Most slender particles move upward in the flow field in the direction of the axis and the mainstream velocity of the flow field. At the height, on the one hand, the existence of slender particles here will lead to the increase of turbulence velocity gradient at this height, which will lead to the increase of turbulent kinetic energy value at the whole height. On the other hand, the existence of slender particles will consume part of the turbulent kinetic energy of the local turbulence field. In the horizontal direction, the turbulent kinetic energy will decrease obviously in the area where the slender particles exist. The existence of slender particles will increase the pressure gradient of the whole turbulent field.
【作者单位】：南京师范大学江苏省能源系统过程转化与减排技术工程实验室;东南大学能源与环境学院;
【基金】：国家自然科学基金项目(51306094) 教育部博士点基金(2014M551490) 江苏省博士后基金(1401003A)~~
【分类号】：O359
【正文快照】： 0引言细长颗粒气固两相流的流变特性研究是细长颗粒气固两相流研究的重点与难点之一[1-6]。细长颗粒是指圆柱状的颗粒,其长度至少是其直径的几倍以上,此时,将其抽象成球形颗粒会导致较大程度的误差。在早期阶段细长颗粒两相流研究中,细长颗粒与流场之间都是单向耦合,即仅

【相似文献】