Dynamic Mode Decomposition Applied to a Detached-Eddy Simulation of Separated Nozzle Flow
Konferensbidrag (offentliggjort, men ej förlagsutgivet), 2017

The paper presents results from a Dynamic Mode Decomposition (DMD) of data from a Detached Eddy Simulation (DES) of a separated flow inside a truncated ideal nozzle. Two cases of different pressure ratios were studied. Sparsity-Promoting algorithm along with computed optimal mode amplitudes were used to determine importance of individual modes. An ovalization mode (a mode with azimuthal wavenumber m = 2) was found for the lower pressure ratio and was linked to a peak in spectra from probe data. At the higher pressure ratio a helical mode (azimuthal wavenumber m = 1) was found and linked to a peak in spectra from probe data and the nozzle side-load spectrum. The paper shows the potential for using DMD for separated nozzle flows to identify im- portant periodic flow behavior but also underlines the challenges that the method faces, such as noise from resolved turbulence and difficulty identifying modes within the broad low-frequency-range of the side-load spectrum.

Dynamic Mode Decomposition

Nozzle Flow

Detached Eddy Simulation

Separated Nozzle Flow

Författare

Ragnar Larusson

Chalmers, Tillämpad mekanik, Strömningslära

Markus Olander Burak

Chalmers, Tillämpad mekanik, Strömningslära

Niklas Andersson

Chalmers, Tillämpad mekanik, Strömningslära

Jan Östlund

GKN Aerospace

Proc. of the 55th AIAA Aerospace Sciences Meeting, AIAA SciTech Forum

Ämneskategorier

Rymd- och flygteknik

Strömningsmekanik och akustik

Infrastruktur

C3SE (Chalmers Centre for Computational Science and Engineering)

DOI

10.2514/6.2017-0527

ISBN

978-162410447-3