Direct Numerical Simulation

A Review of Direct Numerical Simulation in CFD

Direct numerical simulation (DNS) of turbulent flows is reviewed in the present study. DNS is a simulation in computational fluid dynamics in which the Navier-Stokes equations are numerically solved without any turbulence modeling. The full range of spatial scales in turbulent flows should be resolved numerically. There are also several issues arising from boundary condition implementation as well as time integration. All these properties make DNS a very computationally intensive numerical method. DNS has enabled the scientific community to get a deeper insight into the more complicated flow physics which are not easily attained using conventional numerical or even experimental methods. A few examples are discussed and the results are presented. Furthermore, DNS has largely impacted turbulence models and provided further insight into the structure of turbulent flows. Although a great tool for analyzing different fluid flows, at the moment, DNS may not provide a suitable solution to real-world problems, mainly due to high numerical solution costs.