Optimization and Computational Fluid Dynamics - Department of ...

Chapter 1
Introduction
Dominique Thévenin
A book dedicated to optimization applied to practical engineering configurations
must probably start with a warning: “optimization” means much more
than “improvement”! It is indeed a pity that so many researchers and engineers
still employ the terminology “optimization” in the title or abstract of
their publications when they simply mean in practice that starting from a
non-satisfactory configuration, they have tried two or three other ones and
chosen at the end the best case. This is undoubtedly related to optimization,
but in a very minimalistic sense! In the present book optimization means
the design and operation of a system or process to make it as good as
possible in some defined sense
which is the definition proposed by the WiKi dictionary, that can be consulted
under http://en.wiktionary.org/wiki/optimization. As a consequence,
the best possible solution constrained by appropriate conditions should be
found, and not simply a “better” one.
Mathematical optimization methods allowing to identify such a constrained,
best possible solution have been known for a long time, but have
not permeated all engineering disciplines yet. Concerning fluid dynamics more
specifically, the first applications of optimization are found for aeronautical
problems (see, e.g., as a starting point the relevant chapters of the recent publication
by Capasso and Périaux [2]), in particular to improve wing profile
and flight properties (typically, reduce drag). This is a problem with a high
added-value and involves “only” the basic equations of fluid dynamics (Euler
or Navier-Stokes equations, depending on the investigated properties). This
Dominique Thévenin
Lab. of Fluid Dynamics and Technical Flows,
University of Magdeburg “Otto von Guericke”, Germany
(e-mail: thevenin@ovgu.de)
3