High-Fidelity Optimization of Flapping Airfoils for Maximum Propulsive Efficiency
نویسندگان
چکیده
A high order spectral difference (SD) scheme based cost-effective multi-level optimization approach is proposed to optimize the kinematics of flapping airfoils and provide further insights into flapping motions with maximum propulsive efficiency. At the first stage, a gradient-based optimization algorithm is coupled with a second-order SD Navier-Stokes solver to search for the optimal kinematics of a certain airfoil undergoing a combined plunge and pitch motion. Then a high-order SD scheme is used to verify the optimization results and reveal the detailed vortex structures associated with the optimal kinematics of the flapping flight. Several NACA 4-digit airfoils are used in the optimization process. The maximum propulsive efficiency of oscillating NACA0006 and NACA0012 airfoils is more than 50% when the oscillating kinematics is optimized. The optimized propulsive efficiency of thin airfoils is larger than that of thick airfoils.
منابع مشابه
High fidelity numerical simulation of airfoil thickness and kinematics effects on flapping airfoil propulsion
High-fidelity numerical simulations with the spectral difference (SD) method are carried out to investigate the unsteady flow over a series of oscillating NACA 4-digit airfoils. Airfoil thickness and kinematics effects on the flapping airfoil propulsion are highlighted. It is confirmed that the aerodynamic performance of airfoils with different thickness can be very different under the same kin...
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