Abstract: | Long‐flexible fiber orientation under the influence of a flow field is an important engineering problem. One can encounter this problem in many fields. For example in fiber reinforced thermoplastics produced in both injection and compression molding, fiber orientation affect final part properties. Fiber orientation models are constructed for short fibers in a simple shear flow case and though this case is important it is not the general case. In this work we extract rotational friction coefficients from Jeffery's model, create a general case long‐flexible fiber orientation model, and apply it in a simple shear flow. POLYM. COMPOS., 37:2425–2433, 2016. © 2015 Society of Plastics Engineers |