Advanced Rotorcraft Aerodynamic Modules for Flight Testing Support, Simulation and Analysis Navy SBIR FY2004.3 Sol No.: Navy SBIR FY2004.3 Topic No.: N04-257 Topic Title: Advanced Rotorcraft Aerodynamic Modules for Flight Testing Support, Simulation and Analysis Proposal No.: N043-257-0 Firm: Continuum Dynamics, Inc. 34 Lexington Avenue Ewing, New Jersey 08618-2302 Contact: Daniel Wachspress Phone: (609) 538-0444 Web Site: www.continuum-dynamics.com Abstract: Accurate performance prediction is crucial to the simulation, analysis and flight testing support of rotorcraft. In this regard, current analysis tools inadequately model key phenomena like blade dynamic stall, rotor tip loads, and rotor downwash because of their failure to predict the true unsteady three-dimensional nature of the aerodynamic environment near the rotor. Continuum Dynamics, Inc. (CDI) has recently developed breakthrough technologies in real-time lifting panel and free-vortex wake modeling that will allow us to address these issues with unprecedented fidelity at low CPU cost. A new fast lifting surface blade aerodynamics module is proposed building on CDI's state-of-the-art vortex lattice and fast panel solution technology that will, for the first time, allow accurate modeling of three-dimensional rotor tip effects for arbitrarily-shaped rotors in general maneuvering flight. Coupling this new technology with CDI's extensively validated, full-span free-vortex wake model, will provide unparalleled predictions of unsteady loading and details of the rotor flow field for general flight conditions including high rate of descent. Finally, a new efficient, accurate blade dynamic stall model is proposed utilizing an enhanced combination of fast panel/vortex algorithms, rounding out the ability of the solution techniques to model all the crucial aerodynamic phenomena identified in the solicitation. Benefits: A successful Phase1/Phase 2 effort would produce enhanced rotorcraft aerodynamic modules with the ability to accurately model arbitrarily shaped rotors during general steady or maneuvering flight conditions. A real-time fast lifting surface blade aerodynamics model would greatly enhance the current capabilities of both comprehensive design and analysis tools and pilot in the loop simulations to model the unsteady three dimensional aerodynamic effects associated with highly twisted rotor blades and advanced blade shapes such as swept, parabolic and paddle tips. Combining this fast unsteady lifting surface technology with enhanced real-time free wake modeling technology would potentially revolutionize the ability of analysis and simulation codes to accurately predict and model unsteady flow events such as dynamic blade stall, vortex ring state, downwash and the effects of three dimensional rotor aerodynamic shaping during both steady and maneuvering flight. The proposed new aerodynamic modules would greatly enhance the ability of the US Navy's comprehensive rotorcraft analysis and simulation tools to accurately predict rotorcraft performance and thus to support naval flight testing with more confidence. These modules could also support flight testing and research and development work undertaken by major helicopter manufacturers and other branches of the government. Further commercial interest could come from rotorcraft operators, flight training organizations and the manufacturers of flight simulators. Return