2.太原工业学院材料工程系,太原 030008
1.Key Laboratory of Urban Storm Water System and Water Environment, Ministry of Education, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
2.Department of Materials Engineering, Taiyuan Institute of Technology, Taiyuan 030008, China
采用流变仪对不同含固率猪粪的流变性质进行测量,分析其流变特性,将流变数据与非牛顿流体模型进行拟合,得到用于描述猪粪流变特性的最佳流变方程。结果表明:猪粪是一种非牛顿流体,黏度随剪切速率的增加而减小并趋于稳定。基于其流变特性,运用计算流体力学(computational fluid dynamics,CFD)模拟技术,对猪粪厌氧消化反应器内的流场进行研究。模拟结果显示:反应器内速度最大值出现在桨叶末端,猪粪流体在其反应器内的宏观循环运动状态为沿着搅拌轴径向的绕流运动;壁面及顶部和底部区域速度几乎为零,形成死区,容积比率为29.85%。
The rheological curves of pig manure with different solid contents were measured by a rheometer, and its rheological properties were analyzed. Through fitting the rheological data with the non-newtonian fluid model, the optimal rheological equation describing the rheological characteristics of pig manure was obtained. The results showed that pig manure was a non-Newtonian fluid, and its viscosity decreased with the increase of shear rate and then approached stable. Based on its rheological characteristics, the flow field in anaerobic digestion reactor of pig manure was studied by using computational fluid dynamics. The CFD simulation results displayed that the maximum velocity occurred at the vicinity of blade tip, the state of the macroscopically circulating motion of the swine manure in the reactor was the radial flow around the agitating shaft. The velocities at the wall, the top and bottom regions were almost zero, where the dead zones formed with a volume ratio of 29.85%.
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Sketch map of pig manure anaerobic digestion reactor
Geometry of pig manure anaerobic digestion reactor
Mesh partition of the reactor and local refinement of propeller
不同含固率下猪粪的黏度与剪切速率的变化关系
Relationship between viscosity and shear rate of pig manure at different solid rates
Plots of pathlines in the reactor
Dead zone distribution of pig manure anaerobic digestion reactor
Fitting results of the rheological properties of pig manure with a total solid of 20.02% by the common non-Newtonian fluid models
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