Trailing-Edge Noise with Passive Compliant Coating: A Computational Study

A computational study to investigate the role of passive compliant coatings and trailing-edge noise is conducted on a flat plate in fully turbulent flow. Ffowcs Williams and Hawkings model is used to predict far-field noise generated by a flat plate with sharp trailing-edge. Noise was accurately predicted from 750 - 7000 Hz (i.e., St = 4.28 - 40.00), thus demonstrating the validity of this technique. Farfield noise is also predicted for the baseline rigid flat plate model and compared with the case when compliant coating is applied to flat plate. It was observed that application of compliant coating on the flat plate model may result in an increase of trailing-edge noise by 10-15 dB throughout the frequency range of interest, with a reduction in noise of 6 dB at St=4.00. Increase in noise predictions is attributed to the choice of compliant coating material properties. This choice plays a crucial role in determining whether the coating can exhibit the desired response to fluctuating pressure over the compliant wall for a given flowfield. Further computational study is proposed to investigate the relationship between coating's resonance frequency and given flowfield to mitigate trailing-edge noise.