ABSTRACT
Two Eiffel type wind tunnels were used in this study. The size o f the working section is 1.0m (width) x 1.8m (height) for the larger one, and 0.7m (w) x 1.0m (h) for the smaller one. Model size is correspondingly 45mm(2?) x 90mm(D) x 900mm(/) for the larger, and 25mm(2?) x 50mm(Z>) x 600mm(/) for the smaller. Each model has end plates so as to keep the flow around the model two dimensional. The larger one was for the measurement o f Cd, Cl and St in smooth flow and in the applied sound. The smaller one was for the surface pressure measurement in heaving oscillation in smooth flow. 28 pressure taps are installed in a cross section at the center o f model span, (see Fig.2) Fluctuating
Fig.2 2D rectangular cross section model with pressure taps
heaving mode. [3] The maximum frequency o f the applied sound was limited to 40Hz to avoid the resonance in pneumatic and electrical sense. The approaching average wind velocity was measured by the Pitot tube and manometer system, while fluctuating wind velocity components by the hot-wire anemometers (model 1008+1011+1013, Kanomax, Co.Ltd.). The turbulence intensity (o fU ) o f the approaching wind velocity in smooth flow is less than 0.5% in both wind tunnel. All data were simultaneously recorded on the digital data recorder (DR-F1, TEAC Co.Ltd ).
