Virtual Aircraft Technology Integration Platform: Ingredients for Multidisciplinary Simulation and Virtual Flight Testing

Abstract

The development, testing and production of new aircraft are associated with considerable temporal and financial risks due to the product and manufacturing complexity. In order to accelerate the introduction of innovative technologies for more economical, more environmentally friendly and safer air vehicles and to better control the technological risks involved, DLR's guiding concept 'The Virtual Product' aims at virtualizing the design, development and manufacturing processes, including the definition of an appropriate validation strategy. The availability of high-fidelity simulation tools with the capability to model multidisciplinary phenomena is a decisive part in that context. High demands are put on the numerical methods and solvers as the tools must provide reliable results in a robust manner for the entire flight envelope where nonlinearities are prominent in most of the disciplines. A key technology is the ability to enable 'virtual flight testing' based on high-fidelity simulation tools. The progress made at the German Aerospace Center (DLR) in the recent past regarding the development of methods and tools for performing virtual flight tests is presented. The content is split in two papers. The second paper ('Virtual Aircraft Technology Integration Platform: From Virtual Flight Testing towards Simulation-based Certification') presents (for the sake of system identification purposes) virtual flight tests of a medium size short-haul transport aircraft using many of the simulation ingredients described in the present paper. Aerodynamics, structural dynamics, flight mechanics and propulsion are considered in the massively-parallel, time-domain simulation of longitudinal and multi-axis maneuvers. Validations against experimental data of real flight tests for the same aircraft are presented; the accuracy of the virtual flight test approach and the multidisciplinary framework are discussed. The present paper gives an overview of the development status of the building blocks required for virtual flight testing, and it described the simulation framework FlowSimulator used for the integration. Verification and validation aspects concerning the monodisciplinary components and the overall framework are addressed. Further ingredients required for virtual flight testing, including the modeling of atmospheric effects and dynamic deflection of control surfaces, mesh deformation, spatial CFD/CSM coupling, trimming and the development of the next generation CFD solver CODA are described. Selected applications are discussed, demonstrating the capabilities that are available.