The great number of varied approaches to hydrodynamic stability theory
appear as a bulk of results whose classification and discussion are
well-known in the literature. Several books deal with one aspect of this
theory alone (e.g. the linear case, the influence of temperature and
magnetic field, large classes of globally stable fluid motions etc.).
The aim of this book is to provide a complete mathe- matical treatment
of hydrodynamic stability theory by combining the early results of
engineers and applied mathematicians with the recent achievements of
pure mathematicians. In order to ensure a more operational frame to this
theory I have briefly outlined the main results concerning the stability
of the simplest types of flow. I have attempted several definitions of
the stability of fluid flows with due consideration of the connections
between them. On the other hand, as the large number of initial and
boundary value problems in hydrodynamic stability theory requires
appropriate treat- ments, most of this book is devoted to the main
concepts and methods used in hydrodynamic stability theory. Open
problems are expressed in both mathematical and physical terms.