Development and Validation of Full-Aircraft Free-Flight Maneuvering Simulation Using Tightly Coupled CFD-CSD and FCS

This paper demonstrates the recent success of developing a high-fidelity Co-Simulation (CoSim) technology to enable free-flight full-aircraft maneuvers using closed-loop tightly coupled Computational Fluid Dynamics (CFD), Computational Structural Dynamics (CSD) with full-production aircraft Flight Control Systems (FCS). This new development empowers the previous CFD-CSD maneuver simulation with a digital brain from the production aircraft FCS and enables a true high-fidelity predictive capability with significant improvement in the accuracy of the results, removing its dependency on other analysis as inputs. The newly developed CoSim methodology was correlated with S-97 RAIDER® helicopter flight test maneuvers. This study shows that development and usage of the current state-of-the-art methodology, when carefully validated and applied, can capture the complex rotorcraft physics due to fluid and structure interaction during maneuvering flights with sufficient accuracy to support both early stage of design and flight test planning.