Session: 04-08: Emerging Integrated System Applications

Paper Number: 91090

91090 - Power Efficiency of Drag Reduction Using Traveling Waves for Morphing Wing Airfoils 

Traveling waves are widely used by aquatic swimmers as a propulsive mechanism and are presently being investigated for flow control over airfoils.  Recent studies looking at low amplitude actuations on the suction (top) side of the NACA 0018 airfoil have demonstrated increased lift (38.3%), decreased drag (68%) and delayed flow separation, performing better than controlled cases with standing wave actuations.  Significant reductions in drag motivate the question of power efficiency, which is relative to the product of drag force saved and flow velocity.  We ask: is the power saved during drag reduction justified by the power consumed by the electromechanical actuators?  Also, how is the relationship between power input and output affected by different flow parameters and uncertainties?  What are the most sensitive parameters guiding power usage in both the structure and actuator selection?  We look at these questions starting in the abstract and leading up to a fully coupled model including actuator, structure, and interaction with the fluid layer.  Energy in the system undergoes several changes, from electrical, to mechanical, to aerodynamic.  We look at the amplitude-normalized power of bending traveling waves for different materials and stiffnesses, efficiency of electromechanical transducers, and efficiency of the transfer of momentum to the adjacent moving fluid to get a general sense of the parameters affecting power in the system before analyzing the fully coupled multiphysics model.

Presenting Author: Anthony Olivett University At Buffalo