Aerodynamic behavior of microstructures

The lift and drag coefficients, C_L and C_D, were measured for miniature airplane shaped structures, approximately 2 mm in length, made from silicon. The airflow regime surrounding the structures was laminar, similar to that found around comparably sized flying insects. The structures were attached to the tips of finely drawn, 30 μm diameter glass rods, which were then placed inside a laminar fluid flow, with Re ranging from 76 to 207. By measuring the forces on the airplane due to lift and drag, C_L and C_D can be determined. The drag coefficient was found to be relatively independent of attack angle, increasing by only about 50% between 0° and 90°. The experimental results, C_L=0.5-1, and C_D=1-4, were compared to values found using FEM analysis