Dynamic effects on different rotor profiles for eVTOL applications

Resumo

Electric Vertical Take-Off and Landing (eVTOL) aircraft, commonly known as eVTOLs, represent a recent and promising concept for enhancing urban mobility, particularly in densely populated areas. However, the development of eVTOLs has been accompanied by various technical and technological challenges, primarily due to the rapid introduction of new concepts. Among these challenges, this study focuses on investigating the dynamic effects on rotor blades designed for such aircraft. Rotor blades, being subject to rotational dynamic effects, exhibit behavior distinct from components lacking angular velocity. Therefore, they are of particular interest for dynamic analysis. The study begins by defining a simplified geometry representative of a rotor blade, which serves as the basis for applying finite element methods using Ansys software. This approach enables the observation of the system's response to rotation. Following, more detailed geometries representing rotors are modelled, respectively in NACA 0012, VR 08 and VR 12 airfoils, which are then subject to the rotational effects numerical calculations. The results obtained for the different aerodynamic profiles are then compared, presenting the differences caused by the different geometries and mass distributions implied. The results obtained from the analysis highlight the significant impact of angular velocity on the fundamental frequencies and modes of the dynamic system. These findings suggest the presence of effects such as spin softening and strain stiffening, along with identifying important frequency coupling points.