Aerodynamic behavior of microstructures

The lift and drag coefficients, C/sub L/ and C/sub D/, were measured for a miniature airplane shaped structure, approximately 2 mm in length, made from aluminum. The airflow regime surrounding the structure was laminar, similar to that found around comparably sized flying insects. The structures were attached to the tips of finely drawn, 30 /spl mu/m diameter glass rods, which were then placed inside a laminar fluid flow, with Re ranging from 48 to 130. By measuring the displacement of the airplane due to both lift and drag forces, lift and drag coefficients could be determined. The drag coefficient was found to be relatively independent of the attack angle, increasing by only about 50% between 0/spl deg/ and 90/spl deg/. The experimental results, C/sub L/=1 to 2, and C/sub D/=2 to 10, were compared to values found using FEM analysis.<>