[Roh]

Guys,
I'm soppused to solve a problem with this domain. just like this:



I'm using pressure-inlet and pressure-outlet for boundray condition and due to my source, for "Turbulence>Specification Method" I need to set it as "Intensity and Hydraulic Diameter". ok, so far so good. I googled it to know how to calculate them(Intensity and Hydraulic Diameter). For Intensity, found this:

http://www.afs.enea.it/project/neptu...ug/node238.htm

And for Hydraulic Diameter found these:

How to calculate Turbulent Intensity?

hydraulic diameter in 2d

Ok, then for calculating Intensity I need to calculate Reynold's number and for Reynold's number, first off I need to calculate the Hydraulic Diameter. Right? Now the problem is calculating the Hydraulic Diameter. for my two boundary condition I have problem. How should I calculate the Hydraulic Diameter for outlet while the outlet is my domain? And how about the inlet? The inlet area is not a complete circle and it looks like a ring if we look at it at front. Any idea would be appreciated.

[A CFD free user]

Hi,
It is easy.. just do this:
Dh= 4A/P
Where A is the wetted area and P the premiter of the geometry.