Frequency-domain prediction of turbofan noise radiation

Date

2004-03-05

Author

Özyörük, Yusuf
Alpman, E
Ahuja, V
Long, LN

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This paper describes a frequency-domain numerical method for predicting noise radiation from ducted fans, including acoustic treatment and non-uniform background flow effects. The method solves the Euler equations linearized about a mean flow in the frequency domain. A pseudo-time derivative term is added to the frequency-domain equations so that a time marching technique can be employed to drive the acoustic field to steady state explicitly. This approach makes distributed parallel computing more viable for equations of this type and will allow for future use of well-known convergence acceleration techniques, such as multigrid, to obtain the solutions efficiently. Simulations of the JT15D static test inlet are performed including the effects of liners, and the results are compared with experimental data. A generic engine geometry is used for demonstrating further the prediction capability of the code, calculating the attenuation effects of different liner impedances and liner installation locations on the radiated sound fields.

Subject Keywords

Boundary-conditions, Ducted fans, Sound, Computation, Engine, Simulation, Flow

URI

https://hdl.handle.net/11511/32757

Journal

JOURNAL OF SOUND AND VIBRATION

DOI

https://doi.org/10.1016/s0022-460x(03)00640-0

Collections

Department of Aerospace Engineering, Article

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Citation Formats

Y. Özyörük, E. Alpman, V. Ahuja, and L. Long, “Frequency-domain prediction of turbofan noise radiation,” JOURNAL OF SOUND AND VIBRATION, pp. 933–950, 2004, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32757.