Introduction
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on just this fundamental disparity. From general fluid dynamical principles, we
expect the dynamics of each of these regions to differ due to the presence of
differing magnitudes of the fluid accelerations and of the spatial gradients of
the dynamical fields in the two regions.
On the one hand, this promises increased complexity for the analysis of the
dynamics while on the other hand the distinctive dynamics in the various
regions provides the theoretician with an opportunity to exploit the special
dynamic character of each region, profiting from simplifications possible in
each of them. It then remains to fit the pieces of the solution together to
reproduce the unitary natural picture, which is of course independent of the
methodological expedients employed in analysis.