Phase II Final Report - NASA's Institute for Advanced Concepts

Chapter 3.0 Vehicle Design
3.3 Wing Aerodynamics
on the other wing leading to a net-zero force in this direction when taking both wings as a system.
We now present the force’s time history for the case with continuous blowing with blowing
velocity of 1 m/s. No noticeable difference was seen in the results, probably due to the fact that
the blowing speed is so low and the blowing angle was not optimized to take advantage of the
Coanda effect.
Figure 3-101: Force (Newtons) Time History for Case with Continuous Blowing Velocity
of 1 m/s
Additional cycles of results were obtained for this case to confirm periodicity in time.
The wing-flapping motion is of sufficient strength, and the presence of the free stream velocity
(corresponding to forward motion of the wing) carries the wing vortices downstream so that reasonable
periodicity of the motion seems to be achieved essentially from the end of the first
cycle.
3.3.1.7 Conclusions
The results presented in this section represent the first attempts to advance the solution of a very
difficult flapping-wing problem. The plots show that the maximum lift coefficient was around 4
or 5, and with further refinements to blowing techniques, it can be augmented. The present
results reveal several features of low Reynolds aerodynamics that haven't been systematically
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