In this work, Dielectric Barrier Discharge (DBD) plasma actuators were used to control flow-induced tonal and broadband noise radiated from single and tandem cylinders configuration, respectively. The models were examined at free stream velocity of 10 ms~(-1) corresponding to a Reynolds number 1.1 × 10~4. The plasma actuators were positioned at various azimuthal angles ±27° ≤ Ө_j ≤ ±153° on both the upper and lower sides of the cylinder. Both far-field sound pressure level and flow field structure were examined at Brunei University London aerocoustic facility using far field condenser microphone, PIV system, and hot wire anemometer. For the single cylinder case, the far field measurements suggested that a reduction of up to 12 (IB in the sound pressure level can be achieved when plasma actuators are positioned at Ө_j = ±133°. For tandem cylinders configuration, the acoustic results showed that a simultaneous activation of both the upstream and downstream cylinders leads to a further reduction in the narrowband and broadband noise level compared with the other tested cases. The flow control mechanisms related to the narrowband and broadband interaction noise were also discussed.
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