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Advances in Aircraft and Spacecraft Science Volume 1, Number 1, January 2014 , pages 27-41 DOI: https://doi.org/10.12989/aas.2014.1.1.027 |
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Circular cylinder drag reduction using piezoelectric actuators |
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Matteo Orazia, Davide Lasagnab and Gaetano Iuso
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| Abstract | ||
| An active flow control technique based on \'smart-tabs\' is proposed to delay flow separation on a circular cylinder. The actuators are retractable and orientable multilayer piezoelectric tabs which protrude perpendicularly from the model surface. They are mounted along the spanwise direction with constant spacing. The effectiveness of the control was tested in pre-critical and in post-critical regime by evaluating the effects of several control parameters of the tabs like frequency, amplitude, height, angular position and plate incidence with respect to the local flow. Measurements of the mean static pressure distribution around the cylinder were used to estimate the pressure drag coefficient. The maximum drag reduction achieved in the pre-critical regime was of the order of 30%, whereas in the post-critical regime was about 10%, 3% of which due to active forcing. Furthermore, pressure fluctuation measurements were performed and spectral analysis indicated an almost complete suppression of the vortex shedding in active forcing conditions. | ||
| Key Words | ||
| flow control; bluff body; cylinder; drag reduction; piezoelectric actuators; smart tabs | ||
| Address | ||
| Matteo Orazia, Davide Lasagnab and Gaetano Iuso: Dipartimento di Ingegneria Meccanica e Aerospaziale, Politecnico di Torino 24, Corso Duca degli Abruzzi, 10129 Torino, Italy | ||
