Analysis of propulsion-structural coupling characteristics of distributed propulsion wing

Compared with traditional fixed-wing aircraft, distributed propulsion aircraft has advantages in aerodynamic performance, flight control, safety and other aspects. In recent years, aircraft researchers and designers pay attention to it. To achieve higher propulsion/aerodynamic performance, the distributed propulsion units are embedded in the wing, and the propulsion unit components are highly fused with the wing to form the DPW(distributed propulsion wing). The DPW acts as both the wing lift component in forward flight and the duct component of the ducted fan propulsion unit. Compared with the conventional wing, the structure configuration, mass distribution and load distribution of the distributed propulsion wing are more complex and special, and tend to have special structural characteristics, which brings difficulties to its structural analysis and design. Based on this background, modeling, numerical simulation and analysis of propulsion-structural characteristics of DPW structure under propulsive and aerodynamic loads in forward flight are carried out in this paper. Firstly, the research focuses on the modeling method of the distributed propulsion wing. The propulsion-structural parametric model of the distributed propulsion wing is constructed by disassembling each component of the DPW in a reasonable manner. Initially, based on the structural characteristics of the DPW, the wing is divided into unit segments. Subsequently, considering the load distribution characteristics within these segments and their structural force transmission characteristics, the unit was further divided into rotor, stator support, and inner and outer walls. The second step involves using Grasshopper, a visual programming language, to complete geometric parametric modeling of the structure. In the third step, appropriate finite element models are selected based on bearing characteristics of components. Patran and PCL are then utilized to construct parameterized finite element models for the distributed propulsion wing structure, and the effectiveness of the model is verified through structural modal experiments. Then, the propulsive/structural characteristics of the DPW are studied numerically. Based on the parametric model established in this paper, analyse the propulsive/structural characteristics of the DPW by numerical method using Nastran. The focus is on the influence of factors such as the mass of the power units, the layout of the static blades in the power units, and the local structural stiffness on the overall structural dynamics and statics of the DPW. Finally, summary the structural modeling method of distributed propulsion wing then elaborate the correlation between structural characteristics such as structure mass, deformation, load distribution and its structural configuration and characteristic parameters, which provides support for structural analysis and design of distributed propulsion wing.