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

Chapter 3.0 Vehicle Design
3.3 Wing Aerodynamics
about the cicada wing is the layout of the spar-and-rib structure. Unlike aircraft wing, it appears
that the natural wing lends itself to large flexure, which has been observed in experiments with
live insects.
Figure 3-80: North American Cicada Forewings and Right Hind Wing
Figure 3-81: Elliptic Wing Modeled After North American Cicada Wing
3.3.1.5 CFD Analysis: Metacomp Technologies
Metacomp Technologies Inc. was subcontracted to perform (CFD) analyses on the Entomopter
wing. The nature of this very complex problem resulted in a need for more sophisticated techniques
than what was used in the FLUENT and WIND analyses. The goal here was to do more
refined and accurate simulations of the wing motion, with flapping, and with blowing around a
curved trailing edge. This CFD analysis was performed using Mars atmospheric data and flapping
parameters found to be within the design space for a Mars Entomopter. Four cases were
run:
1. No Flapping steady forward velocity, NO BLOWING
2. No Flapping steady forward velocity, BLOWN
3. Flapping with steady forward velocity, NO BLOWING
4. Flapping with steady forward velocity, BLOWN
The purpose of the non-flapping cases was to determine the degree to which the CFD could
accurately simulate the Coanda effect due to the blowing over a trailing edge surface (curved
flap). This known, one could then segregate the effects of blowing in the flapping cases from
those created by the flapping itself.
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