An inverse method for rheometry of power-law fluids
An inverse method for rheometry of power-law fluids
复制标题
DOI：
10.1088/0957-0233/22/12/125402
复制
发表时间：
2011-12-01
影响因子：
2.4
通讯作者：
Rees, Julia M.
中科院分区：
文献类型：
--
作者：
Bandulasena, H. C. Hemaka;Zimmerman, William B.;Rees, Julia M.
本文涉及通过反演方法结合偏微分方程控制系统的有限元建模来确定黄原胶稀溶液的本构粘性参数。在低浓度下，黄原胶表现为剪切稀化、幂律非牛顿流体。有限元建模用于模拟微通道 T 形接头中黄原胶溶液的压力驱动流动。当流体被迫转向 T 形接头的拐角时，会产生一定范围的剪切速率，从而产生粘度。结果表明，速度场的统计特性对幂律模型的本构参数敏感。反演方法稳定且准确，速度场中的测量误差转化为流变参数估计中的小误差。由于逆映射的特殊结构，误差传播远小于哈达玛准则的估计。
This paper is concerned with the determination of the constitutive viscous parameters of dilute solutions of xanthan gum by means of an inverse method used in conjunction with finite element modeling of the governing system of partial differential equations. At low concentrations xanthan gum behaves as a shear-thinning, power-law non-Newtonian fluid. Finite element modeling is used to simulate the pressure-driven flow of xanthan gum solutions in a microchannel T-junction. As the flow is forced to turn the corner of the T-junction a range of shear rates, and hence viscosities, is produced. It is shown that the statistical properties of the velocity field are sensitive to the constitutive parameters of the power-law model. The inverse method is shown to be stable and accurate, with measurement error in the velocity field translating to small errors in the rheological parameter estimation. Due to the particular structure of the inverse map, the error propagation is substantially less than the estimate from the Hadamard criterion.