how to ensure that your modelling is correct

rvndr

Hi

I am a beginner and want to know the answer for this questions ?Suppose you are modelling some problem in CFD, which has numerical solution or experimental result. In this case you will compare your CFD result with the experimental result.

On the other hand, now suppose you are modelling some problem which has no experimental result. Then in this case how will you ensure that your CFD modelling result is correct ?

one more thing is if you already have experimental result then what is the need for going CFD modelling again ?

This questions may not sounds well but you have to bare with me as I am a beginner.Thanks in advance

rvndr