Student: Andrew Bodling, Graduate Student in Aerospace Engineering; Wind Energy Science, Engineering and Policy (Co-Majors) Iowa State University
Faculty Advisor: Anupam Sharma
Numerical Investigations of Bio-Inspired Blade Designs
Noise generated from wind turbines and jet engines can be a real nuisance to anyone living nearby them and is a serious issue to address to allow people residing near them 
to accept their presence. In our research project, we are seeking to solve the noise problem with turbine blades by taking a bio-inspired approach. We are researching the nocturnal owl to understand what makes the bird so quiet during flight in an effort to create nearly silent aircraft, UAVs and wind turbines.
For a part of my thesis that I’m currently working on, I am modeling one of the pertinent anatomical features of the owl, the soft downy coat, and investigating how it attenuates sound. I am simulating the soft downy coat using the extensively validated, high order accurate Navier Stokes solver FDL3DI. The owl-inspired geometry simulated was suggested by Clark et al. (2014), which used “fences” near the trailing edge of the airfoil to simulate the canopy effect of the owl feathers. Although there is much work to be done, early results of the research are promising. The fences simulated have shown to reduce the sound spectra in the high frequencies by up to 1.8 dB at the airfoil trailing edge. The fences showed a reduction in the spanwise coherence length, especially at low frequencies. The simulation results also showed that the fence spacing and front curvature are important design parameters. Future work will analyze the radiated farfield noise and will simulate higher Reynolds numbers that match more closely with the experiments of Clark et al. (2014).