Hi! I'm lecturer in Fluid Dynamics. For my first post, I thought I'd share our paper that was just published in JFM (it's open access)
https://www.cambridge.org/core/journals/journal-of-fluid-mechanics/article/instability-in-strongly-stratified-plane-couette-flow-with-application-to-supercritical-fluids/B32FE078ADB51FA9B5E72BCD25755319

It's about an instability in shear flows that feature strong variations of properties (such as density and viscosity)