请问，Fluent软件的层流模型是怎么一回事？

wangshangfei

请问，Fluent软件的层流模型是怎么一回事？和直接数值模拟有区别吗？

turbulencest

In the manual, there are no points that mention Fluent can setup DNS. However, the personal opinions from one guy from Fluent Inc are as follows:
"
1. In principal, Fluent can do the DNS. You will need to choose the L­aminar model in Define --> Model --> Viscous panel. This will ensure that no empirical model is used and you are solving the pure Navier stoke equation.
2. The DNS at the high Reynolds number needs that mesh should be fine enough to capture smallest of eddies. The mesh quality is also of importance, and you need a very good quality hexahedral mesh with skewness approaching zero and aspect ratio approaching one. Also, to capture the transient behavior of eddies; the simulation should be set-up as unsteady simulations.
Considering all this factors, DNS simulations need huge computational resources both in terms of computation time as well as disk storage.
3. While using the DNS, you need to make sure that numerical diffusion is as small as possible. Higher order discretization schemes are must for DNS simulation.
Hence, in principal DNS can be done with existing models. However, the very high computational requirements put a question on practical use of the same."