  The hydrodynamic processes operating within stellar interiors are far richer
than represented by the best stellar evolution model available. Although it is
now widely understood, through astrophysical simulation and relevant
terrestrial experiment, that many of the basic assumptions which underlie our
treatments of stellar evolution are flawed, we lack a suitable, comprehensive
replacement. This is due to a deficiency in our fundamental understanding of
the transport and mixing properties of a turbulent, reactive, magnetized
plasma; a deficiency in knowledge which stems from the richness and variety of
solutions which characterize the inherently non-linear set of governing
equations. The exponential increase in availability of computing resources,
however, is ushering in a new era of understanding complex hydrodynamic flows;
and although this field is still in its formative stages, the sophistication
already achieved is leading to a dramatic paradigm shift in how we model
astrophysical fluid dynamics. We highlight here some recent results from a
series of multi-dimensional stellar interior calculations which are part of a
program designed to improve our one-dimensional treatment of massive star
evolution and stellar evolution in general.
