BISPECTRAL MODE DECOMPOSITION FOR DISCOVERY AND MODELING OF NONLINEAR FLOW PHYSICS IN OPEN CAVITY FLOWS
Abstract
The proposed work explores the potential of Bispectral Mode Decomposition (BMD) for the physical discovery and reduced-order modeling of nonlinear flow phenomena in turbulent open cavity flows. This technique applies to both numerical and experimental data, similar to the Proper Orthogonal Decomposition (POD) and the Dynamic Mode Decomposition (DMD). Both POD and DMD extract important flow features and yield accurate low-dimensional representations of the nonlinear flow dynamics. However, neither POD nor DMD gives direct and quantitative insight into the nonlinear interactions that dictate these dynamics. BMD provides this critical capability. BMD was recently introduced and can identify the flow structures associated with the dominant frequency triads as well as their regions of interaction. Open cavity flows exhibit rich nonlinear dynamics comprised of complex interactions between shear-layer instabilities, acoustic pressure waves, and low-frequency oscillations. The stochastic nature of turbulent cavity flows further complicates this picture at the technically relevant Reynolds numbers considered in this work.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 20, 2023
- Source ID
- FA95502210541
Entities
People
- Oliver Schmidt
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of California, San Diego