SCD News > Announcement: June 3, 2005

IMAGe/GTP seminar June 3: "Baroclinic vorticity production in protoplanetary disks and vorticity characterization using the Okubo-Weiss parameter"

Presented by

Date, time, location:

Friday, June 3, 2005
2:00 p.m.
Foothills Bldg. 2, Room 1001

Abstract

Long-lived anti-cyclonic vortices in protoplanetary disks assist planetary formation by concentrating matter at the vortex core. Here we investigate vortex formation and longevity in protoplanetary disks using a reduced, coupled set of equations for vorticity and temperature which include baroclinic vorticity production and thermal damping. Numerical simulations with initial temperature perturbations and zero initial vorticity produce coherent, long-lived vortices within several orbital periods. This study identifies regions of parameter space where shear due to differential rotation inhibits vortex formation, as well as regions of parameter space where strong vortices form.

I will also discuss a second project, where the vorticity field from 2D and 3D quasi-geostrophic turbulence is separated into components using the Okubo-Weiss parameter. The three components are: vortex cores; the circulation cells surrounding the cores; and the background, which contains filaments. Statistics such as energy spectra and velocity probability density functions demonstrate that properties of the full field can be traced to particular components.

For more information, contact Liz Rothney at ext. 1351, rothney@ucar.edu .