English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Three eigenvalue bounds are derived for the instability of ideal compressiblestratified magnetohydrodynamic shear flows in which the base velocity, density,and magnetic field vary in two directions. The first bound can be obtained bycombining the Howard semi-circle theorem with the energy principle of theLagrangian displacement. Remarkably, no special conditions are needed to usethis bound, and for some cases, we can establish the stability of the flow. Thesecond and third bounds come out from a generalisation of the Miles-Howardtheory and have some similarity to the semi-ellipse theorem by Kochar & Jain(J. Fluid Mech., vol. 91, 1979, 489) and the bound found by Cally (Astrophys.Fluid Dyn., vol. 31,1983, 43), respectively. An important byproduct of thisinvestigation is that the Miles-Howard stability condition holds only whenthere is no applied magnetic field and, in addition, the directions of theshear and the stratification are aligned everywhere.

Eigenvalue bounds for compressible stratified magneto-shear flows varying in two transverse directions