Results from recent LES studies of high-speed jet flows and its near and far-field noise (Mendez et al. AIAA-2010-271) are reviewed with an emphasis on validation of the LES results. Far-field noise is predicted using data collected on a conical FW-H surface. Very good agreement with the measurement reported by Bridges & Wernet (AIAA-2008-2834) is observed. Data analysis of the flow disturbances within the jet and in the near-field is used to better characterize the sound source processes. We analyze LES data of Bodony and Lele (Phys. Fluids, vol. 46, 2005) using a filter in the wavenumber-frequency domain. The supersonic components of pressure and radial velocity fluctuation show peaks within the jet and show the Uj8 scaling behavior consistent with the far-field radiated noise levels. The observed scaling is also consistent with a perturbation expansion of nearly incompressible turbulent fluctuations within the jet flow. Linear global mode analysis of the non-parallel jet mean flow is performed. Features of Mach wave radiation are evident in the global modes for supersonic convection. Large transient growth is found due to convective non-normality. Some implications of this analysis for jet noise modeling are discussed. © 2010 Published by Elsevier Ltd.
Lele, S. K., Mendez, S., Ryu, J., Nichols, J., Shoeybi, M., & Moin, P. (2010). Reprint of: Sources of high-speed jet noise: Analysis of les data and modeling. In Procedia IUTAM (Vol. 1, pp. 84–93). Elsevier B.V. https://doi.org/10.1016/j.piutam.2010.10.010