Mathematical Models in Hydrodynamics
نویسنده
چکیده
Mathematical modeling plays an important role whenever flow investigations are performed. In this paper special emphasis was given to models which are used in turbulent flow simulations and the effect of numerical discretization. The numerical scheme is of great importance when direct numerical simulations, i.e. the solution of the Navier-Stokes equations without any additional turbulence model, are performed. Applying DNS only flows with low to moderate Reynolds numbers can be studied, because the physics demand for very fine grids in order to resolve even the smallest turbulent scales. Numerical schemes which content artificial dissipation damp the evolution of the turbulent structures and cannot be used in DNS. For the example of the turbulent flow through a straight pipe, the possibilities and the accuracy of DNS were discussed.
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