Measurement and similarity analysis of boundary layer wall pressure fluctuation in large-scale revolution body models

The measurements for transition frequency-space spectrum and its spectral peak characteristics, turbulent wall pressure fluctuation and its similarity are conducted in acoustic wind tunnel through embedded flush-mounted flexible sensor arrays, regarding two large-scale revolution body models. The numerical fitting model of wall pressure fluctuation in the transition and turbulent regions can be established, in which Reynolds number can serve as frequency segmentation point, and the model is characterized by universality to some extent. It is showed that the local Reynolds number in the transition region at the bow of revolution body is 5.27 × 10⁵ – 1.1 × 10⁶, and the wall pressure fluctuation within the frequency range of transition characteristic spectrum increases by 36 dB from the initial to the fully developed transition stage. Besides, non-dimensional center frequency of transition characteristic spectrum is essentially unchanged at 0.2. The non-dimensional fluctuation pressure spectrum in the turbulent region is in the range of 0.1 to 10, which is in accordance with that of Smol’yakov model. In addition, the non-dimensional spectrum of turbulent fluctuation pressure has scale effects of 3–4 dB in the ranges of 0.4 to 4 for the same model, while it has scale effects of 4 dB in the ranges of 0.1 to 10 for different scale models, in which the non-dimensional spectrum increases by enlargement of the model.