Franco Ediguer E, Adamowski Julio C, Higuti Ricardo T, Buiochi Flávio
Escola Politecnica da Universidade de Sao Paulo, Sao Paulo, Brazil.
IEEE Trans Ultrason Ferroelectr Freq Control. 2008 Oct;55(10):2247-53. doi: 10.1109/TUFFC.923.
This work presents the implementation of the ultrasonic shear reflectance method for viscosity measurement of Newtonian liquids using wave mode conversion from longitudinal to shear waves and vice versa. The method is based on the measurement of the complex reflection coefficient (magnitude and phase) at a solid-liquid interface. The implemented measurement cell is composed of an ultrasonic transducer, a water buffer, an aluminum prism, a PMMA buffer rod, and a sample chamber. Viscosity measurements were made in the range from 1 to 3.5 MHz for olive oil and for automotive oils (SAE 40, 90, and 250) at 15 and 22.5 degrees C, respectively. Moreover, olive oil and corn oil measurements were conducted in the range from 15 to 30 degrees C at 3.5 and 2.25 MHz, respectively. The ultrasonic measurements, in the case of the less viscous liquids, agree with the results provided by a rotational viscometer, showing Newtonian behavior. In the case of the more viscous liquids, a significant difference was obtained, showing a clear non-Newtonian behavior that cannot be described by the Kelvin-Voigt model.
这项工作展示了利用纵波与剪切波之间的波模式转换来测量牛顿液体粘度的超声剪切反射法的实现过程，反之亦然。该方法基于对固液界面处复反射系数（幅度和相位）的测量。所实现的测量单元由一个超声换能器、一个水缓冲器、一个铝棱镜、一根聚甲基丙烯酸甲酯缓冲棒和一个样品腔组成。分别在15摄氏度和22.5摄氏度下，对橄榄油和汽车油（SAE 40、90和250）在1至3.5兆赫兹范围内进行了粘度测量。此外，分别在3.5兆赫兹和2.25兆赫兹下，对橄榄油和玉米油在15至30摄氏度范围内进行了测量。对于粘度较小的液体，超声测量结果与旋转粘度计提供的结果一致，呈现出牛顿流体行为。对于粘度较大的液体，则获得了显著差异，呈现出明显的非牛顿流体行为，这种行为无法用开尔文 - 沃伊特模型来描述。
