Modal Analysis for Open Cavity Flows

Using spectral modal analysis to uncover nonlinear flow phenomena and develop reduced-order models in turbulent open cavity flows. Focuses on shear-layer instabilities, acoustic pressure waves, and low-frequency oscillations at turbulent Reynolds numbers.

Selected Publications

2025

Spectral Proper Orthogonal Decomposition of Transitional Flow Over an Open Cavity

F. O. Aguirre, O. T. Schmidt, and M. A. Medeiros

AIAA Paper 2025-3454, 2025

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This study investigates boundary layer transition over an open cavity under subsonic flow conditions, motivated by the economic and environmental impact of reducing aerodynamic drag. Using Direct Numerical Simulation (DNS), Linear Stability Theory (LST), and Spectral Proper Orthogonal Decomposition (SPOD), the research examines how cavity-induced instabilities, such as Rossiter (acoustic feedback-driven) and centrifugal modes, interact to drive transition, building on prior work linking surface imperfections to bypass transition mechanisms. Results reveal nonlinear couplings between these modes, with Rossiter modes persisting into turbulent regions and centrifugal instabilities introducing three-dimensional flow distortions, highlighting their combined role in destabilizing the boundary layer.