Analysis of polymer jet motion in the non-isothermal melt-blown process

Abstract

The motion characteristic of the polymer jet in a non-isothermal airflow field during melt blowing plays a crucial role in the process of fiber formation and has always been difficult to measure in situ. Many numerical models have been established to simulate the motion of the polymer jet during melt blowing. However, the complex interplay between the airflow field and the polymer jet in these models was usually missed. Here, a coupled air–polymer two-phase flow model in the non-isothermal airflow field was developed by the level-set method, and the temperature dependence of viscosity and density for the polymer jet were also taken into account in our model. Based on the model, the motion of the polymer jet in the melt-blowing process was simulated considering the coupled effect between the air and the polymer jet. The velocities of the polymer jet along x-direction ([Formula: see text]) and y-direction ([Formula: see text]), the whipping amplitude of the polymer jet motion, and the final diameter were discussed and verified. In addition, the effects of critical parameters, such as the inlet airflow velocity, inlet polymer flow velocity, inlet air temperature, and polymer viscosity, on the motion characteristics and temperature of the polymer jet were analyzed numerically.