[LuckyTran]

You do laminar when the flow is laminar and turbulent when the flow is turbulent.


You use steady when the flow is steady and transient when the flow is transient.

[FMDenaro]

Originally Posted by vidyadhar

Hello Lucky Tran,
Thank you for the reply.
If I want to simulate a natural convection problem over a heat sink, how can I decide that I have to use Laminar analysis or turbulent analysis when I change parameters like heat supply to the heat sink, dimensions of the heat sink etc.

If I have to do Laminar analysis, how to decide whether to chose steady state simulation or transient simulation.. if I am interested in steady state solution.


Thanks in advance!
vidyadhar

If you run a transient solver and your solution has a physical steady state, you will reach it after the time derivatives vanish. Conversely, running a steady state solver in a flow problem that does not admit a physical steady state will drive you to get oscillations in the residuals.
In any case, you need to know the physics of your problem if you want to do a correct CFD analysis.
A CFD code is only a stupid numerical algnorithm, it says nothing if you are not able to understand what you are doing