Consideration of failure loads in the preliminary sizing of an aircraft moveable at Virtual Product House

Abstract

In the development of aircraft moveables, one is faced with the challenge that dimensioning states can arise due to the consideration of failure cases, which, however, are not yet available at the time of structural sizing as they require at least a simulation model with realistic stiffness distributions. In general, it would be desirable to use virtual test methods in order to be able to take feedback from the tests into account earlier during product development and thus reduce development risks. For this purpose, a virtual end-to-end process is developed in the DLR Virtual Product House. It considers design, manufacturing and testing and is currently demonstrated for a multifunctional moveable of a research aircraft configuration. Based on a CPACS description of the use case we can automatically determine aerodynamic loads and size the structure accordingly. The resulting structure is translated into a modal representation that can be integrated into a multi-body simulation model. In the next step a co-simulation with a model of the actuation system is performed in order to evaluate different failure cases. A novel extension of the CPACS schema allows the storage of resulting failure loads associated to a specific aircraft configuration and flight state in order to use them for re-evaluation of the structural sizing criteria and to close the loop between testing and design. Due to the end-to-end nature of this process, iterations can be performed until convergence between sizing and failure loads is achieved. In the present text we describe the implementations of the approach with a special emphasis on its continuity. Exemplary results are shown for the wing and moveable use case and a drive shaft failure case.