Modal decomposition of Unsteady Aerodynamic Flows

Project Name Funding Body Industrial Partners Academic/Research Partners Duration
Modal decomposition of Unsteady Aerodynamic Flows FNRS N/A University of Liège Aerodynamics Group 2008-2012

The modal decomposition of unsteady flowfields was proposed in the 1990s by several authors. Proper Orthogonal Decomposition (POD) is one method that can be used in order to perform this modal decomposition; it became popular for aerodynamics research in the 2000s, although it was first proposed for use in fluid dynamics in the 1960s.

This project has two main objectives: to acquire and install Particle Image Velocimetry (PIV) hardware for the ULg Wind Tunnel; and to use the new hardware in order to visualize and decompose unsteady flowfields. The instrumentation has now been purchased and installed. Here we present some sample results for the flow around a circular cylinder.

A circular cylinder in the ULg Wind Tunnel, illuminated by a PIV laser sheet

Velocity vectors (top) and energy contours (bottom) for flow behind a circular cylinder

First (top) and second (bottom) modes of flow behind circular cylinder obtained by POD

Generalized coordinates of flow behind circular cylinder obtained by POD

References