In the fiber spinning process, polymer filaments are extruded through a spinneret and rapidly elongated by a high draw-down velocity. Due to the heat transfer between the filament surface and the cooling medium, the temperature of the filament decreases and crystallization can occur. Crystallinity increases as the filament moves toward the take-up device. Additionally, the process involves a free surface undergoing large deformations, as the fiber is drawn down, with a strong dependence of the material properties on temperature and crystallinity. Thus, there are many challenges in fiber product and process design.

Our CFD software enables you to optimize fiber spinning operating conditions, design spinnerets and quench boxes, and achieve higher fiber quality and production rates.

Modeling PET hollow fiber spinning. This figure shows the predicted temperature distribution. Results also include velocity, tensile stress, and the influence of processing conditions on solidification and spinning dynamics.

Fiber shape and temperature contours predicted for 3D triad fiber spinning of polypropylene. The nonuniformity of temperature distribution in fiber cross-section (on the left) can affect significantly the spinning dynamics and fiber shape.

Modeling multi-fiber spinning through a quenching chamber. Fibers colored by temperature.

Modeling of round fiber spinning. The predicted filament diameter agrees quantitatively with the experimental observations of Bheda and Spruiell [J. Appl. Polym. Sci. 39 (1990) 447-463]. Results also include velocity, temperature, tensile stress, crystallinity and birefringence.