Aerodynamic Characteristics of a Z-Shaped Folding Wing

Abstract

Z-shaped folding wings have the potential to enhance the flight performance of an aircraft, contingent upon its mission requirements. However, the current scope of research on unmanned aerial vehicles (UAVs) with Z-shaped folding wings primarily focuses on the analysis of their folding structure and aeroelasticity-related vibrations. Computational fluid dynamics methods and dynamic meshing are employed to examine the folding process of Z-shaped folding wings. By comparing the steady aerodynamic characteristics of Z-shaped folding wings with those of conventional wings, this investigation explores the dynamic aerodynamic properties of Z-shaped folding wings at varying upward folding speeds. The numerical findings reveal that the folding of Z-shaped folding wings reduces the lift-to-drag ratio, yet simultaneously diminishes the nose-down pitching moment, thereby augmenting maneuverability. Concerning unsteady aerodynamics, the transient lift and drag coefficients of the folded wing initially increase and subsequently decrease as the folding angle increases at small angles of attack. Likewise, the nose-down pitching moment exhibits the same pattern in response to the folding angle. Additionally, the aerodynamic coefficients experience a slight decrease during the initial half of the folding process with increasing folding speed. Once the wing reaches approximately 40°~45° of folding, there is an abrupt change in the transient aerodynamic coefficients. Notably, this abrupt change is delayed with higher folding speeds, eventually converging to similar values across different folding speeds.

Flutter Characteristics of a Modified Z-Shaped Folding Wing Using a New Non-Intrusive Model

“…The coupling relationship between structural and aerodynamics models was proposed innovatively with interpolation between the structural generalized coordinates and incremental normal vectors on the collocation points of aerodynamic panels. Huang et al [18] employed computational fluid dynamics methods and dynamic meshing to examine the folding process of Z-shaped folding wings to explore the dynamic aerodynamic properties of Z-shaped folding wings at varying upward folding speeds.…”

Gust Modeling with State-of-the-Art Computational Fluid Dynamics (CFD) Software and Its Influence on the Aerodynamic Characteristics of an Unmanned Aerial Vehicle

“…Let us notice that there is variety of publications on UAVs aerodynamics, which includes numerical analysis [27], as well as combined experimental and CFD investigation [28,29]. The purposes of the identified works are mostly aerodynamic shape optimization [30] or examination of the influence of flight conditions on the aerodynamic characteristics of UAVs [31,32], which is also a topic of the presented work.…”