Application of Hybrid Methodology to Rotors in Steady and Maneuvering Flight

Previous numerical work in CFD-CSD coupling has extensively been validated for the UH-60A rotor. The motivation behind this work is to validate the CFD-CSD coupling framework for multiple rotor configurations in various flight conditions. The first part of this paper presents calculations obtained using CFD-CSD coupling for MD900 and Apache rotors in steady forward flight using a hybrid wake coupling methodology. The UH-60A rotor has also been used to validate the coupling framework. The loose coupling calculations obtain better power predictions for the MD900 rotor. Thrust sweep calculations were obtained for the UH-60A with reasonable agreement with test data. The preliminary solutions for the Apache rotor show steady convergence characteristics. The second part of this paper investigates the applicability of loose coupling for quasi-steady simulations of slow maneuvers. The steady and maximum load factor segments of the UTTAS 11029 maneuver was studied. The normal forces and pitching moments exhibit good agreement with test data. The study showed that reasonable predictions can be obtained using loose coupling methodology for steady flight and slow maneuvers for multiple rotor configurations.