How to Judge Turbulence Kinetic Energy
 

Hello there,


I have a transient simulation result for two very similar cases. There is only a small change in the geometry of one case and I'm looking at how this geometrical change effects the flow field.


Most of the quantities seem not effected, such as time averaged velocity, pressure, vectors and some additional variables I generated myself which are related to the product. All of these quantities are almost identical to the point where I'm making the conclusion that this geometrical change has no effect in the flow field.


The only big difference I see between two cases is: tke and eddy viscosity. When I plot these two quantities, one case has very high tke values compared to other one, but I don't know how to judge this? Everything else seems very similar but tke contours are two different stories.


Why? How can almost all major quantities be same but tke can still vary significantly? How can you interpret this outcome?

You need to give more details... and pictures would help as well.

In general, three things I can think of:

1) They are very different in distribution but both are either not significant in absolute terms or equally high, so that the specific distribution doesn't matter, only the overall background level

2) In one of them you have a "production spot" but its effects are, somehow, transported away in a zone where they are much less relevant (e.g., uniform flow)

3) One of the cases has not achieved convergence or, however, you are looking at something wrong