MEASUREMENT OF THE TURBULENT BOUNDARY-LAYER WAVE-VECTOR SPECTRUM

Wave-vector filter measurements have been made with the objective of improving quantitative knowledge of the flow excitation function. Two hydrophone arrays with the same number of elements but with different spacings were used. The more closely spaced array covers high-wavenumber characteristics of the convective region of the turbulent boundary layer pressure fluctuations, whereas the other array covers the lower-wavenumber region where contaminants associated with the experimental arrangement also usually exist. Measured results (dB re: 1 μPa2/Hz) are presented as amplitude contour plots as a function of the two wave-vector components at various frequencies. Wave-vector components associated with free-plate vibrations in the low-wavenumber domain were also identified in the results measured using the larger array. © 1990, Acoustical Society of America. All rights reserved.