Eigenvalue Bounds in an Azimuthal Instability Problem of Inviscid Swirling Flows

Authors

  • S. Prakash
  • M. Subbiah

DOI:

https://doi.org/10.18311/jims/2022/29629

Keywords:

Instability, Swirling Flows, Variable Density, Azimuthal Modes, Annulus Region.

Abstract

We consider the eigenvalue problem of azimuthal instability of inviscid swirling ows between coaxial cylinders. It is shown that the complex eigenvalues corresponding to unstable azimuthal normal modes lie inside a semi-ellipse type region whose major axis coincides with the range of the angular velocity of the basic ow while its minor axis depends on the minimum Richardson number, the azimuthal wave number, and the width of the annular region between the coaxial cylinders.

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Published

2022-08-23

How to Cite

Prakash, S., & Subbiah, M. (2022). Eigenvalue Bounds in an Azimuthal Instability Problem of Inviscid Swirling Flows. The Journal of the Indian Mathematical Society, 89(3-4), 387–405. https://doi.org/10.18311/jims/2022/29629