A Numerical Study on the Sound Radiation by Turbulent Jets Based on a Wavepacket Sound-Source Model
Resumen
Prior to the 1950s, turbulence in jet flow was considered to be entirely composed of stochastic structures characterized by their integral turbulence scales, which led to the assumption of spatially decorrelated and compact sound sources. However, several studies showed that coherent structures in turbulent jets play the role of sound sources producing far-field pressure fluctuations [1–3]. Therefore, a theoretical model relating the hydrodynamic sound source to the generated pressure field was necessary to predict the features of the sound radiated by turbulent jets and conceive noise reduction strategies. The key to develop a sound radiation model was the observation by Crow and Champagne [4] and Moore [5], among others, that coherent structures in turbulent jets propagate as wavepackets, from which prominent statistical features of the acoustic field, such as cross-spectral density (CSD) and averaged amplitude and phase, can be drawn in good agreement with experimental data. [...]
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E. Mollo-Christensen. “Jet Noise and Shear Flow Instability Seen From an Experimente’s Viewpoint”. Em: Journal of Applied Mechanics 34.1 (1967), pp. 1–7.
J.C. Lau, M.J. Fisher e H.V. Fuchs. “The intrinsic structure of turbulent jets”. Em: Journal of Sound and Vibration 22.4 (1972), pp. 379–406. issn: 0022-460X. doi: https://doi.org/10.1016/0022-460X(72)90451-8.
D. E. S. Breakey, P. Jordan, A V. G. Cavalieri, P. A. Nogueira, L Olivier, T. Colonius e D. Rodríguez. “Experimental study of turbulent-jet wave packets and their acoustic efficiency”. Em: Phys. Rev. Fluids 2 (12 2017), p. 124601. doi: 10.1103/PhysRevFluids.2.124601. url: https://link.aps.org/doi/10.1103/PhysRevFluids.2.124601.
S. C. Crow e F. H. Champagne. “Orderly structure in jet turbulence”. Em: Journal of Fluid Mechanics 48.3 (1971), pp. 547–591. doi: 10.1017/S0022112071001745.
C. J. Moore. “The role of shear-layer instability waves in jet exhaust noise”. Em: Journal of Fluid Mechanics 80.2 (1977), pp. 321–367. doi: 10.1017/S0022112077001700.
A. V. G. Cavalieri, T. Rodrigues D. J. Colonius e Y. Gervais. “Wavepackets in the velocity field of turbulent jets”. Em: Journal of Fluid Mechanics (2013), pp. 559–592.
A. V. G. Cavalieri e A. Agarwal. “Coherence decay and its impact on sound radiation by wavepackets”. Em: Journal of Fluid Mechanics 748 (2014), pp. 399–415. doi: 10.1017/jfm.2014.186.
A. V. G. Cavalieri, P. Jordan e L. Lesshafft. “Wave-packet models for jet dynamics and sound radiation”. Em: Applied Mechanics Reviews (2019). doi: 10.1115/1.4042736.
