Prediction of ducted diaphragm noise using a stochastic approach with adapted temporal filters

Date

2019-01-01

Author

Karban, Ugur
Schram, Christophe
Sovardi, Carlo
Polifke, Wolfgang

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

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The noise production by ducted single- and double-diaphragm configurations is simulated using a stochastic noise generation and radiation numerical method. The importance of modeling correctly the anisotropy and temporal de-correlation is discussed, based on numerical results obtained by large eddy simulation. A new temporal filter is proposed, designed to provide the targeted spectral decay of energy in an Eulerian reference frame. An anisotropy correction is implemented using a non-linear model. The acoustic propagation problem is solved using Lighthill's aeroacoustic analogy with a tailored Green's function obtained analytically. Comparison with scale-resolved data indicates that accurate far-field noise predictions are obtained for both single and double diaphragm configurations, with computational costs significantly reduced with respect to the scale-resolved approach. A grouping scheme for the noise sources based on the octree structure is introduced to minimize the memory requirements and further reduce the computational cost.

Subject Keywords

Acoustics and Ultrasonics, Aerospace Engineering

URI

https://hdl.handle.net/11511/67504

Journal

INTERNATIONAL JOURNAL OF AEROACOUSTICS

DOI

https://doi.org/10.1177/1475472x18812811

Collections

Engineering, Article

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Citation Formats

U. Karban, C. Schram, C. Sovardi, and W. Polifke, “Prediction of ducted diaphragm noise using a stochastic approach with adapted temporal filters,” INTERNATIONAL JOURNAL OF AEROACOUSTICS, pp. 49–72, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/67504.