| dc.description.abstract | The idea that guided the first French edition of the present book was to give to
newcomers in Fluid Dynamics a presentation of the field that was anchored in
Physics rather than in Applied Mathematics as it had been the case so often in
the past. Presently, however, connections with Physics are getting stronger and this
is fortunate. Indeed, Physics is, etymologically, the science of Nature and fluids
occupy a major place in Nature. They are everywhere around us and their motion
(their mechanics) influences our everyday life, at least through the weather. Any
physicist can hardly escape being fascinated by the sight of some remarkable fluid
flows like breaking waves or the gently travelling smoke ring.
The connection between Fluid Mechanics and Applied Mathematics is certainly
understandable by the very small number of equations that control a fluid flow.
This is fascinating for an applied mathematician, especially if keen on the theory of
partial differential equations. Actually, a few decades ago, expertise in asymptotic
expansions, singular perturbations, and othermathematical technics was a necessary
condition to make progress in the theory of fluid flows. But the pressure of maths
has certainly lessened in the recent times because of the strong (exponential) growth
of numerical simulations. It is now easier to experiment numerically a fluid flow and
get a detailed description of the solutions of Navier–Stokes equation. Interpretation
of the results may challenge the intuition of the physicist rather than the skill of the
mathematician. But even in the pioneering times, when theoretical investigations
of fluid flows were at the strength of the pencil, famous physicists like Newton,
Maxwell, Kelvin, Rayleigh, Heisenberg, Landau, Chandrasekhar, and others made
essential contributions to the field of Fluid Dynamics. As noted by Heisenberg
himself, the theory of turbulence awaits to be written, and this is still the case. | en_US |
