Investigation on improved preliminary sizing processes of aircraft structures under dynamic loads

Kurzfassung

In order to consider a large number of design loads within the preliminary sizing process of aircraft structures in reasonable computational times, typically dynamic simulations are performed using simple stick models. These models consist of FE beam elements and concentrated. For the preliminary sizing, the dynamic internal loads obtained from the dynamic simulations are converted to static load sets that are applied to a detailed 3D FE representation of the aircraft. The combination of using the simple stick model as well as the conversion of the dynamic internal loads to static load sets leads to rather conservative designs. In this paper, an improved preliminary sizing process for dynamic load cases is presented. Two enhanced design processes are described, utilized and finally compared to the current design process. The used case for this study is built up by a generic aircraft which is subjected to different landing load cases. The first improvement of the design process removes the usage of static load sets for the preliminary sizing, while still allowing to utilize a simple stick model for the dynamic simulations. The second improvement also removes the stick model in the dynamic simulations and replaces it with a detailed 3D representation of the aircraft. In order to assess the potential weight savings, the stress distributions throughout the fuselage of the generic aircraft are studied and compared to each other.