Simuleringsbaserade processer för framtagning av strukturlaster

Determining structural loads from flight simulation

Goals/targets: The project aims to increase the efficiency of the flight loads prediction process, primarily by means of integrating structural states into the flight simulation. In this way, structural loads can be obtained directly or (depending on the states selected) extracted by standard procedures, without the need for a time-consuming and possibly too conservative load reconstruction process. Furthermore, the accuracy of the flight simulation can be improved by taking structural deformations and their effect on aerodynamic loads into account. Result and effects: The interaction between the state of the aircraft and flight loads used for structural design is currently somewhat weak, since simulation models used for flight simulation do not involve states representing structural deformations. This requires a rather time consuming postprocessing of flight simulation results to reconstruct the aircraft loads from a series of reference load cases. There is a need for a more efficient process reducing the engineering work load. The methods developed in the project will also make it possible to integrate unsteady aerodynamic loads and aeroelastic effects in flight simulation increasing fidelity. The improved fidelity can reduce the structural weight penalties caused by overly conservative load predictions using a more traditional approach. The need for more efficient aircraft load analysis is also expected to increase by the participation in the EU Clean Sky Smart Fixed Wing project. For the type of configurations considered in this project, aeroelastic load cases such as gust loads may be critical for the structure and consequently for the aircraft mass. Determination of accurate gust loads can be quite time consuming using more traditional methods and the methods developed in the project will improve both the efficiency and accuracy of gust load analysis. Planning and implementing The project is performed in a sequence of phases. The first phase is primarily concerned with theoretical issues and development of methods with results presented in reports and publications. Then follows a phase focused on software development and analysis of a set of reference cases of realistic complexity. The aim is to develop useful software for engineering analysis and design. Feedback from industrial use will then be used to refine the computational tools developed.