Understanding the effective viscosity of fiber-filled polymer melts is essential for predicting the local fiber orientation of injection molded short-fiber reinforced components. To circumvent the intrinsic difficulties of experimentally determining the strongly anisotropic viscosity of such particle-reinforced melts, an FFT-based computational homogenization method for computing the effective quasi-static viscosity of a particle-suspended Newton fluid is introduced, based on a dual formulation.

The dependence of the effective viscosity on microstructural parameters, like fiber volume fraction, fiber aspect ratio and fiber orientation are investigated by computational experiments on representative volume elements, and the results are compared to an analytical model for the effective viscosity. Based on the computational findings, a closed-form approximation for the effective viscosity is provided.

了解纤维填充聚合物熔体的有效粘度对于预测注塑短纤维增强部件的局部纤维取向至关重要。为了规避实验确定这种颗粒增强熔体的强各向异性粘度的固有困难，引入了一种基于 FFT 的计算均质化方法，用于计算颗粒悬浮牛顿流体的有效准静态粘度，基于双重公式。

通过对代表性体积元素的计算实验研究了有效粘度对微观结构参数（如纤维体积分数、纤维纵横比和纤维取向）的依赖性，并将结果与​​有效粘度的分析模型进行了比较。基于计算结果，提供了有效粘度的封闭形式近似值。