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Title: Broadband reconstruction of inhomogeneous turbulence using spectral proper orthogonal decomposition and Gabor modes
A new methodology to construct three-dimensional, temporally stationary but spatially inhomogeneous, incompressible turbulence is presented. The method combines use of the data-driven spectral proper orthogonal decomposition (SPOD) to identify and isolate large-scale coherent motions of the flow, together with a physics-based enrichment algorithm using spatiotemporally localized Gabor modes that capture the inertial range turbulence. This fusion of data-driven and physics-based methods enables a statistically correct reconstruction of broadband turbulent flows using fewer modes than would be required using SPOD alone. To demonstrate the approach, we consider the problem of reconstructing wake turbulence on a plane downstream of a dragging actuator disk impinged by homogeneous isotropic turbulence. The reconstructed flow has single- and two-point correlations that are consistent with the reference high-resolution simulation data and could be used to generate statistically consistent inflow boundary conditions for subsequent simulations.  more » « less
Award ID(s):
1803378
PAR ID:
10173429
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Journal of fluid mechanics
Volume:
888
ISSN:
1469-7645
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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