“On the Use of Mean Flow Perturbation for Global Stability Analysis”
Publication Type:
Conference
Authors:
Co-Authors:
R. Rajan and D. Gaitonde
Year Published:
2018
Abstract:
The effectiveness of a Navier-Stokes based Mean Flow Perturbation (NS-MFP) technique in obtaining linear response of basic states upon application of small perturbation is demonstrated. The method solves the full non-linear Navier-Stokes equations in the time domain, using forcing to maintain the invariance of the basic state. When subjected to a random impulse perturbation field, the evolution of the perturbations is incorporated into a series of snapshots. A subsequent dynamic mode decomposition (DMD) analysis of these snapshots yields relevant instability modes, their growth rates as well as associated frequencies. This technique is thus couched as a robust matrix-free approach for the global stability analysis. NS-MFP along with DMD is used to analyze the stability of 2-D regularized lid-driven cavity (LDC) flows. The results compare favorably with established global modes available from traditional analyses. The major advantage of the technique is that it can be applied fairly easily to complex 3-D flows, including those in which compressibility is important, in a relatively efficient manner.
Conference Name:
2018 Fluid Dynamics Conference, AIAA Aviation Forum
Conference Location:
Atlanta, Georgia
Other Numbers:
Refereed Designation:
Date Published:
6/24/2018