[en] The paper compares the unsteady airflow field in the conventional and the new dual-feed rotor spinning unit. A 3D finite volume computation (with optional turbulence model) is adopted to simulate the airflow dynamics with a focus on the rotor interior. The equations are solved using Fluent 14.5 package. The airflow results reveal that the second transfer channel effect is significant, particularly in the rotor interior. Visualization of iso-surfaces and velocity magnitude in the two reveal a striking difference in the internal flow patterns and turbulent strength. Comparison of the yarn properties spun on the two systems shows improved tenacity, elongation, and yarn evenness. A Small variation in yarn hairiness of the respective spun samples is observed. (paper)