Wavelet-based resolvent analysis for statistically-stationary and temporally-evolving flows
Abstract
This work introduces a formulation of resolvent analysis that uses wavelet transforms rather than Fourier transforms in time. This allows resolvent analysis to be extended to turbulent flows with non-stationary means in addition to statistically-stationary flows. The optimal resolvent modes for this formulation correspond to the potentially time-transient structures that are most amplified by the linearized Navier-Stokes operator. We validate this methodology for turbulent channel flow and show that the wavelet-based and Fourier-based resolvent analyses are equivalent for statistically-stationary flows. We then apply the wavelet-based resolvent analysis to study the transient growth mechanism in the buffer layer of a turbulent channel flow by windowing the resolvent operator in time and frequency. The method is also applied to temporally-evolving parallel shear flows such as an oscillating boundary layer and three-dimensional channel flow, in which a lateral pressure gradient perturbs a fully-developed turbulent flow in a channel.
Additional Information
© 2023 by Eric Ballouz, Barbara Lopez-Doriga, Scott T. M. Dawson, H. Jane Bae.Additional details
- Eprint ID
- 120470
- Resolver ID
- CaltechAUTHORS:20230327-902843000.16
- Created
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2023-03-30Created from EPrint's datestamp field
- Updated
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2023-03-30Created from EPrint's last_modified field
- Caltech groups
- GALCIT
- Other Numbering System Name
- AIAA Paper
- Other Numbering System Identifier
- 2023-0676