摘要
采用旋转粘度计测定了不同含固率、温度条件下新鲜猪粪的流变曲线,并对含固率、温度对猪粪流变特性的影响进行了分析。结果表明:猪粪为假塑性流体且符合幂率方程。表观粘度随含固率的增大呈现增大趋势,但温度对其影响不大;表观粘度与含固率曲线存在临界点,可以作为非牛顿流体(猪粪)近似视为牛顿流体的标准;表观粘度与剪切速率曲线也存在一个临界D值,提出搅拌死区可以从剪切速度角度来定义。同时对温度影响猪粪表观粘度的机理进行了讨论;最后对表观粘度与含固率、剪切速率的关系进行了多元非线性回归分析,建立了表观粘度模型且拟合效果很好,为涉及非牛顿流体(猪粪)的工艺设计和优化提供了函数形式的物性参数关系式。
Rheological curves of pig manure with different solid holdup and temperatures were measured by a rotational viscometer. The effects of solid holdup and temperatures on the rheological behaviors were studied. The results indicated that pig manure behaved like pseudoplastic fluid and followed the power law model. The apparent viscosity showed an ＂upward growth＂ trend with the increase of solid holdup, but the temperature had little influence on it. There were some critical points on viscosity and solid curves, and they could be used as the standard of non-Newtonian fluid （pig manure） regarded as Newtonian approximately. There were also some critical D values on viscosity and shear rate curves, proposing that they could be used as definition of dead zone. The mechanism for temperature affecting apparent viscosity was discussed. Finally, the relationship between analyzed apparent viscosity and solid holdup and shear rate with the help of multiple nonlinear regression were analyzed, and a mathematical model was established and fittted well with experimental results, which provided the relationship of physical parameters in the functional form for process design and optimization involving non-Newtonian fluid （pig manure）
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2014年第2期188-193,共6页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家自然科学基金资助项目(51078287)
关键词
猪粪
流变特性
含固率临界点
剪切速率临界点
表观粘度模型
Pig manure Rheological properties Solid holdup critical point Shear rate critical pointApparent viscosity model
