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Clarifying Low-Frequency Variatoions Phenomenon Using a Novel Mode Decomposition Method

Published online by Cambridge University Press:  05 May 2011

C.-T. Wang
C.-T. Wang*
Affiliation:
Department of Mechanical Engineering, National I Lan University, I Lan, Taiwan 26047, R.O.C.
*
* Assistant Professor
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Abstract

Low-frequency variations in wake flow are complex and many aspects of its behavior remain poorly understood. A mode decomposition method developed by Huang et al is utilized herein because it can decompose any complicated data set into a finite number of intrinsic modes without distorting their original characteristics. The results of decomposition analysis of the measured base pressure signals reveal that a finite number of various kinds of flow structure modes, with their own characteristic time scales, coexist with the residue that exhibits most of the low-frequency variations in flow at Re = 11760 and 31600, respectively. As the Reynolds number increases, the decomposition method yields more components. Results also show exactly the vortex shedding structure in an intrinsic mode and the low-frequency variations that appear in the residue during vortex shedding process.

Keywords

Low-frequency variationMode decomposition analysis
Type
Articles
Information
Journal of Mechanics , Volume 22 , Issue 3 , September 2006 , pp. 193 - 198
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2006

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