Review of Turbulent Boundary Layer Models for Acoustic Analysis

A survey of the available turbulent boundary-layer models for acoustic analysis is presented. The empirical mean-square pressure models predict a relatively large spread in the values: bounded on the high end by the Kraichnan model and on the low end by the Bull model and the Willmarth and Wooldridge model. It is difficult to select a preferred model based on data from the Spirit model 6 x 6 in. duct. The single-point wall-pressure spectrum models are evaluated, and the two more modern Smol'yakov and Goody models seem to perform the best. The single-point wall-pressure spectrums from the Spirit model 6 x 6 in. data at low frequencies roll off similar to the Goody model, indicating that it is the preferred model for aircraft applications. Important features of the normalized wavenumber-frequency spectrum models are presented. Separable models in the Corcos model class tend to overpredict the response for a range of cases. The nonseparable Chase 1 and Smol'yakov-Tkachenko models match the Massachusetts Institute of Technology low-noise low-turbulence wind-tunnel data throughout the range of comparison. The Chase 1 model can be converted from the wavenumber-frequency spectrum to the cross spectrum, so it is the preferred model for aircraft applications. [PUBLICATION ABSTRACT]