Aerodynamic Optimization and Torque Analysis of a Rotating Cross-Slit Cylinder with End Deflector Plate through Frozen Rotor modelling

This research focused on optimizing the aerodynamics and analyzing the torque of a rotating cross-slit cylinder equipped with an end deflector plate, utilizing the Frozen Rotor modeling method. The main aim was to improve the cylinder's aerodynamic efficiency and comprehend its torque characteristics, which are crucial in applications like wind-energy harvesting and vehicle aerodynamics. The study assessed how the cross-slit design and deflector plate affected flow separation, drag reduction, and torque generation across different rotational speeds. The frozen-rotor modeling approach was used to simulate the steady-state flow field, effectively capturing the rotational motion's impact and the intricate interactions between the deflector plate and the surrounding airflow. By employing parametric studies and optimization techniques, the study quantified how various design configurations influenced aerodynamic efficiency and torque output. The findings underscore the end deflector plate's pivotal role in altering flow patterns, minimizing drag, and enhancing torque production, offering valuable insights for designing more efficient rotating systems in engineering contexts. The study concludes with a set of optimized design parameters aimed at improving aerodynamic performance in similar fluid-structure interaction scenarios.
Data were collected at various downstream locations (x/D = 15–50) to offer a detailed depiction of the near-field wake dynamics in the presence of deflector plates. The time-averaged flow field highlights the persistence and development of coherent structures formed by the interaction between slit-induced vortices and rotational influences. At x/D = 15 and 20, there was noticeable asymmetry and organized vortex pairs, indicating active vortex shedding affected by the Magnus effect. As the flow progresses downstream (x/D = 25–35), the wake starts to expand and weaken, showing signs of vortex breakdown and energy dissipation. By the time it reaches x/D = 40 and 50, the flow field becomes more diffused, with diminished vorticity intensity and less distinct shear layers. This extended observation confirms that the combination of cross-slit geometry and rotation significantly impacts the wake's stability and structure over time.
Deflector plates are crucial in reducing wake oscillations and aiding flow recovery. These findings suggest that the design strategy effectively delays wake instabilities and facilitates smoother flow transitions, which are beneficial for applications focused on drag reduction, noise control, and improved aerodynamic performance. Increasing the Reynolds number enhances surface vorticity and three-dimensional flow effects. The angular configuration and slit design greatly affect the wake structure and aerodynamic forces. Cross-slit cylinders surpass traditional designs in lift generation with lower torque penalties.