Numerical prediction of aft radiation of turbofan tones through exhaust jets

Date

2009-08-07

Author

Özyörük, Yusuf

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

172
views

0
downloads

This paper describes a numerical methodology for calculating tonal noise propagation and radiation through turbomachinery exhaust ducts, including non-uniform background jet flows. The numerical method is based on solution of the linearized Euler equations directly in the frequency domain, employing a direct, sparse matrix solver in parallel. Acoustic sources are introduced into the computational domain via the perfectly matched layer equations. Various test cases including propagation through infinite ducts, and propagation and radiation through semi-infinite ducts with and without liners are solved, and results are compared with analytical solutions. It is demonstrated that solutions even with thin shear layers separating the exterior and jet streams at reasonably high Mach numbers can be obtained quite successfully. The method is also validated by simulating the radiated sound waves from two actual engine exhaust cowl geometries, and the results are compared with experimental data.

Subject Keywords

COMPUTATION, NOISE

URI

https://hdl.handle.net/11511/49276

Journal

JOURNAL OF SOUND AND VIBRATION

DOI

https://doi.org/10.1016/j.jsv.2009.03.012

Collections

Department of Aerospace Engineering, Article

Suggestions

OpenMETU
Core

Frequency-domain prediction of turbofan noise radiation Özyörük, Yusuf; Alpman, E; Ahuja, V; Long, LN (2004-03-05) 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 fo...
Development of high performance long wavelength infrared HgCdTe focal plane arrays Barutçu, Berna; Beşikci, Cengiz; Department of Electrical and Electronics Engineering (2019) This thesis study reports the characterization of long wavelength infrared (LWIR) HgCdTe photovoltaic detectors with the p on n structure and 9.5 μm cut-off wavelength grown by molecular beam epitaxy on CdZnTe substrates and fabricated with different passivation processes. The characterization study was conducted at both pixel and focal plane array (FPA) levels. While the detectors exhibit diffusion dominated dark current at temperatures at and above 130 K under reverse bias voltages typically used in imagi...
Numerical investigation of coupled heat and mass transfer inside the adsorbent bed of an adsorption cooling unit Solmus, Ismail; Rees, D. Andrew S.; Yamali, Cemil; Baker, Derek Keıth; KAFTANOĞLU, BİLGİN (2012-05-01) In this study, the influence of several design parameters on the transient distributions of temperature, pressure and amount adsorbed in the radial direction of a cylindrical adsorbent bed of an adsorption cooling unit using silica gel/water have been investigated numerically. For this purpose, a transient one-dimensional local thermal non-equilibrium model that accounts for both internal and external mass transfer resistances has been developed using the local volume averaging method. For the conditions in...
Numerical and experimental investigation of tubeaxial fan noise Bodur, Ahmet; Çalışkan, Mehmet; Department of Mechanical Engineering (2014) In this study, the noise characteristic of a tube axial fan is investigated numerically and experimentally. The effects of blockage plate in front of the tube axial fan on the tube axial fan noise level are experimentally investigated. A computational aero-acoustic method is used to predict the flow induced fan noise. This method couples a flow solver and a wave equation solver. Unsteady flow analysis is performed with URANS (Unsteady Reynolds Average Navier Stokes Equation) method while acoustics radiation...
Comparison of PWM and PFM induction drives ID in,egarding audible noise and vibration for household applications Ertan, Hulusi Bülent (2004-11-01) This paper is aimed at comparing the performance of pulse frequency modulation (PFM) and pulsewidth modulation (PWM) techniques regarding audible noise generated from inverter-driven induction motors. For the purpose of illustrating the performance of the two modulation techniques, a drive developed for washing machine applications is considered. First, the measured and simulated harmonic content of this inverter is compared with the measured harmonic spectrum of a three-phase input-output commercial variab...

Citation Formats

Y. Özyörük, “Numerical prediction of aft radiation of turbofan tones through exhaust jets,” JOURNAL OF SOUND AND VIBRATION, pp. 122–144, 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/49276.