## Section: Application Domains

### Turbulence

Turbulent flows are ubiquitous in industrial applications. Direct numerical simulation (DNS), which aims at complete resolution of the flow field up to the Kolmogorov scale, has historically been limited to very simple geometries. The increase of computational power and the development of specialized numerical methods open the door to a wider range of applications. However, for most applications of practical interest, the use of some kind of turbulence modeling is unavoidable in order to obtain the prediction of averaged values and commercial software is in general based on such approaches combined with wall laws. In many applications, such as the project Optimal, see Section 7.1 , the Reynolds number is at an intermediate level, which means that the turbulence is not fully developed, and the heuristics behind most turbulence models are questionable. Especially, in heat transfer problems, the usage of wall laws seems to considerably lower the accuracy of the predicted mean values. In order to improve the computation of such values, we are particularly interested in variational multiscale methods and its relations to stabilized finite element methods.