Performances of rotational shear rheometers are sometimes limited to measuring low viscosity at high temperatures of water-based polymer solutions. These limitations are typically due to the instrument resolution, sample inertia, and volumetric effects. Moreover, such measurements are not possible for temperatures exceeding 80 °C because of evaporation phenomena leading to a distortion of the value. The working principle of rheometers suitable for measuring viscosity above the boiling temperature reduces their sensitivity and limits their use to high-viscosity fluids. Acrylamide-based polymers are viscoelastic complex fluids exhibiting non-Newtonian behavior. Their viscosifying properties are strongly related to their charge density, molar mass, temperature, and salinity. The prediction of their rheological properties at high temperatures is challenging and is often extrapolated with an empiric law, such as Arrhenius equation. To the best of our knowledge, no commercially available rheometers are capable of measuring low viscosity of water-soluble complex fluids at high temperatures. In this work, we investigate a home-made fully automated capillary rheometer that has been developed to give an accurate measurement of viscosity and intrinsic viscosity of polymer solutions. This device is an affordable cost portable apparatus compared with a commercialized rheometer specifically designed for a wide range of viscosities and temperatures for various applications. The intrinsic viscosity has been measured on two acrylamide-based polymers of different chemical compositions using the capillary rheometer at high temperatures. This device has also been explored for measurement of a water-soluble polymer solution viscosity commonly used in enhanced oil recovery applications to limit chemical degradation.

中文翻译：

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便携式流变仪克服了在高温下测量丙烯酰胺基聚合物的低粘度溶液的挑战，而且成本低廉，适用于石油和天然气应用

旋转剪切流变仪的性能有时仅限于测量水基聚合物溶液在高温下的低粘度。这些限制通常是由于仪器分辨率、样品惯性和体积效应造成的。此外，由于蒸发现象会导致数值失真，因此无法在超过 80 °C 的温度下进行此类测量。适合测量高于沸点温度的粘度的流变仪的工作原理降低了它们的灵敏度并限制了它们对高粘度流体的使用。基于丙烯酰胺的聚合物是具有非牛顿行为的粘弹性复杂流体。它们的增粘特性与其电荷密度、摩尔质量、温度和盐度密切相关。它们在高温下的流变特性的预测具有挑战性，通常用经验定律外推，例如阿伦尼乌斯方程。据我们所知，没有市售的流变仪能够在高温下测量水溶性复杂流体的低粘度。在这项工作中，我们研究了一种自制的全自动毛细管流变仪，该流变仪已被开发用于准确测量聚合物溶液的粘度和特性粘度。与专为各种应用的各种粘度和温度而设计的商业化流变仪相比，该设备是一种经济实惠的便携式设备。使用毛细管流变仪在高温下测量了两种不同化学成分的丙烯酰胺基聚合物的特性粘度。该设备还被用于测量水溶性聚合物溶液粘度，该粘度通常用于提高采油率应用以限制化学降解。