Using the power of NCSA's new Itanium Linux cluster, a University of Minnesota research team will be able to simulate turbulent flow in greater detail than ever before possible.

Anyone who has traveled on an airplane is aware of turbulence. This atmospheric phenomenon, which makes your tray table jiggle and leads the captain to turn on the "fasten seat belts" sign, is caused by instabilities of shear flow that result from atmospheric convection. This turbulence, although annoying and sometimes unnerving, pales in comparison to the supersonic turbulence found in the outer envelopes of red giant stars.

Simulations of convection in such stars by Paul Woodward's team at the University of Minnesota's Laboratory for Computational Science and Engineering (LCSE) show that heat rising from the interior of a star stirs up the outer envelope of the star and can result in gas motions that exceed the speed of sound near the stellar surface. These turbulent convective motions give rise to shocks—sudden compressions of the gas—of Mach 2 or more.

Access Online | Posted 11-13-2001