Assessment of an iterative approach for solution of frequency domain linearized euler equations for noise propagation through turbofan jet flows

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2007

Author

Dizemen, İlke Evrim

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This study, explores the use of an iterative solution approach for the linearized Euler equations formulated in the frequency domain for fan tone noise propagation and radiation through bypass jets. The aim is to be able to simulate high frequency propagation and radiation phenomena with this code, without excessive computational resources. All computations are performed in parallel using MPI library routines on a computer cluster. The linearized Euler equations support the Kelvin-Helmholtz type convective physical instabilities in jet shear flows. If these equations are solved directly in frequency domain, the unstable modes may be filtered out for the frequencies of interest. However, direct solutions are memory intensive and the reachable frequency is limited. Results provided shown that iterative solution of LEE is more efficient when considered memory requirement and might solve a wider scope of frequencies, if the instabilities are controlled.

Subject Keywords

Aerospace engineering., Aeronautical engineering.

URI

http://etd.lib.metu.edu.tr/upload/12609095/index.pdf
https://hdl.handle.net/11511/17359

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

İ. E. Dizemen, “Assessment of an iterative approach for solution of frequency domain linearized euler equations for noise propagation through turbofan jet flows,” M.S. - Master of Science, Middle East Technical University, 2007.