A viscosity overshoot of fibers filled in a polymer melt under a shear flow is much tougher to predict via the existing constitutive equations of suspension rheology in a viscous media, owing to the effect of fiber orientation on the viscoelastic behavior. The WMT-X (White–Metzner model eXtended by Tseng) viscoelastic fluid model coupled with the typical Dinh–Armstrong fiber suspension model, known as the suspended WMT-X model, is proposed herein. The primary procedure involves verifying the lower viscosity of the completely aligned suspension compared to that of the randomly oriented suspension. In addition, the viscosity overshoot depends on the off-diagonal orientation tensor component in the flow-gradient plane. As a validation, the numerical predictions of transient shear viscosity are in good agreement with the related experimental data.

中文翻译：

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粘弹性介质中纤维悬浮液的本构方程

由于纤维取向对粘弹性行为的影响，在剪切流下填充在聚合物熔体中的纤维的粘度超调更难以通过粘性介质中悬浮流变学的现有本构方程进行预测。WMT-X（由 Tseng 扩展的 White-Metzner 模型）粘弹性流体模型与典型的 Dinh-Armstrong 纤维悬浮模型相结合，称为悬浮WMT-X 模型，在此提出。主要程序包括验证与随机取向的悬浮液相比，完全排列的悬浮液的粘度较低。此外，粘度超调取决于流动梯度平面中的非对角取向张量分量。作为验证，瞬态剪切粘度的数值预测与相关实验数据非常吻合。