R.M. Kerr and M. Oliver,
The ever-elusive blowup in the mathematical description of fluids,
in: "An Invitation to Mathematics: From Competitions to Research," D. Schleicher and M. Lackmann (eds.), pp. 137-164, Springer-Verlag, Berlin, 2011.

Abstract:

This contribution introduces you to the Euler equations of ideal fluids and the Navier-Stokes equations which govern fully developed turbulent flows. We describe some of the unresolved mathematical issues, including the "Navier-Stokes millennium problem", and the role numerical simulations play in developing this field.
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