Frequency domain computation of turbofan exhaust noise radiation

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Date

2006

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Ulusoy, Yavuz Barbaros

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In this study, acoustic noise radiation through a duct in frequency domain is analyzed. Frequency domain linearized Euler equations are solved for turbofan exhaust noise propagation and radiation. The geometry in studied cases is assumed as axisymmetric. The acoustic waves are decomposed into periodic azimuthal modes. Characteristic boundary conditions, and buffer zone boundary conditions are employed. Iterative type pseudo time integration is employed. Nonuniform background flow effect on the radiation pattern is experienced. All computations are performed in parallel using MPI library routines in computer cluster. Results proved that the one with the buffer zone has a better radiation characteristic than the characteristic one because of absorbtion of spurious waves. It is seen that the efficiency of the buffer zone is frequency dependent.

Subject Keywords

Motor vehicles.

URI

http://etd.lib.metu.edu.tr/upload/12607234/index.pdf
https://hdl.handle.net/11511/15890

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

Y. B. Ulusoy, “Frequency domain computation of turbofan exhaust noise radiation,” M.S. - Master of Science, Middle East Technical University, 2006.