基于欧拉模型的叶片式抛送装置内气固两相流模拟

发布时间：2018-01-01 04:14

本文关键词：基于欧拉模型的叶片式抛送装置内气固两相流模拟　出处：《内蒙古工业大学》2014年硕士论文　论文类型：学位论文

【摘要】：为弄清叶片式抛送装置工作时其内部物料和气流的真实流动情况和分布规律，本文借助CFD（ComputationalFluid Dynamic）软件Fluent6.3对装置内部的气固两相流流场进行三维数值模拟计算，获得了抛送物料过程中装置内两相流场的压力及速度分布状况以及物料运动规律，同时对叶片式抛送装置主要工作参数对两相流场及物料运动的影响进行对比分析。本文在分析了叶片式抛送装置工作原理基础上，建立了基于Eulerian模型的叶片式抛送装置内气固两相流数学模型；创建了装置的三维实体模型及流道模型，，并分区对其进行网格划分；确定了该装置内气固两相流数值模拟方法：采用Eulerian模型和标准k-ε湍流模型，选用simple算法对装置内部流场进行数值模拟；将物料速度仿真计算结果与文献[15]相同工况下高速摄像实测数据进行比较分析，在验证模拟结果可靠基础上，进行了装置主要工作参数对物料运动影响的对比分析。经数值计算，本文得出：1.叶片数为四时，与叶片数为三和五比较，压力场分布对称均匀且速度场的涡流区域较小，抛送性能较好。2.进料速度对物料的流场分布影响很大；进料速度为13.5m/s时装置既不会造成堵塞，又能在单位时间抛出更多的物料，抛送效率较高，为此工况下的最佳进料速度。3.进料口物料体积浓度变化仅改变叶轮以及出料管区的物料浓度，进料口处物料体积浓度越大，整个区域的物料体积浓度越大；而对物料速度分布规律及大小影响不大。4.叶轮叶片安装时倾斜一定角度有利于物料抛送，叶片后倾10o时叶轮区速度分布更为均匀，涡流小，有利于抛送效率的提高。5.叶轮转速的提高有利于流场内物料流场的均匀化和出口速度的提高。其中叶片数、叶片倾角以及叶轮转速对装置工作性能的影响与抛送装置工作性能试验结果基本一致，进一步验证了仿真结果的可靠性。本课题的研究为叶片式抛送装置的进一步改进设计提供依据。
[Abstract]:Throwing device to work in order to clarify the internal material and vane airflow real flow and distribution, with the aid of CFD (ComputationalFluid Dynamic) software Fluent6.3 on the device inside the gas-solid two-phase flow field of three-dimensional numerical simulation, the pressure and velocity distribution and movement of material flow within the device to throw things the material in the process of comparative analysis and throwing device main working parameters of vane type of two-phase flow and material movement.
Based on the analysis of the leaf blower based on the working principle of the blade type Eulerian model throwing device in gas-solid two-phase flow mathematical model based on; to create three-dimensional entity model and channel model of the device, and partition mesh; determine the device in gas-solid two-phase numerical simulation method flow: the Eulerian model and the standard k- turbulence model and simple algorithm is adopted to simulate the flow field inside the device; the material velocity simulation results and literature [15] under the same conditions of high-speed camera measurement data comparison analysis, the simulation result is reliable on the basis of comparative analysis of the impact of the main parameters of the working device of material movement.
By numerical calculation, the paper concludes: 1. leaf number and leaf number was four, three and five compared to small eddy current region pressure field distribution symmetry and velocity field, the throwing performance.2. feed speed material has great influence on flow field distribution; feed speed of 13.5m/s device is not blocked, it can throw more material in unit time, throwing for higher efficiency, under the condition of optimum feed speed of.3. inlet material volume concentration changes only change the impeller and material concentration area, inlet material volume concentration and the volume of material concentration in the whole region of the greater; influence of material velocity distribution and the size is small.4. impeller blade installation angle for material throwing blades, backward 10o impeller more uniform velocity distribution, eddy current is small, is conducive to improve the efficiency of the.5. cast send impeller Is conducive to the material flow field flow field uniformity and exit velocity of raising speed increased. The leaf number, leaf angle and impeller speed effect on device performance and throwing device performance test results are basically consistent, further verify the reliability of the simulation results. This study provides a basis for further polishing blade type improved design of feeding device.

【学位授予单位】：内蒙古工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TH238;O359

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