This paper numerically models an airfoil geometry inspired by the downy coat of the barn owl and contrasts its aerodynamic and aeroacoustic performance with the baseline airfoil. Implicit large eddy simulations are performed with the Navier Stokes solver FDL3DI. A baseline NACA 0012 airfoil is compared against the same model with an array of fences at the trailing edge. Both models were simulated at a Reynolds number of 3 × 105, flow mach number of 0.2 and angle of attack of 3 degrees.
The fences are shown to reduce the sound spectra in the high frequencies by up to 1.8 dB at the airfoil trailing edge. Spanwise correlations show a reduction in coherence length, especially at low frequencies, with the fences. The simulation results agree with the experiments in that the fence spacing is an important design parameter.
Available at: http://works.bepress.com/anupam_sharma/38/
This is a manuscript of a proceeding published as Bodling, Andrew, Bharat R. Agrawal, Anupam Sharma, Ian Clark, William N. Alexander, and William J. Devenport. 2017. "Numerical Investigations of Bio-Inspired Blade Designs to Reduce Broadband Noise in Aircraft Engines and Wind Turbines." 55th AIAA Aerospace Sciences Meeting, AIAA SciTech Forum, (AIAA 2017-0458). DOI: 10.2514/6.2017-0458. Posted with permission.