[Coatilque]

Hello everybody!
I've got a problem - I'm trying to do an analysis of heating pipe. I need to create a mesh and boundary layer which will look how this one:


I recently started working with Ansys and I don't know how to create a mesh like this... What should I do step by step? I've already created a geometry and extruded it:


Now I need to create a mesh. I've tried to do it by sweep method:


but it didn't work as you see... I guess that I should create a point in centre of circle and maybe do mapped face meshing? How to do step by step this regular mesh?

Thanks in advance for any help you can give me

[flotus1]

Is there any specific reason why you want such a mesh? You will get bad quality elements in the center of the channel while refining the mesh.
I cant help you with this one, but here is an alternative.

[Coatilque]

I've tried to do this like You recommed. I got something like this:


I'm doing analysis for my thesis. My thesis supervisor gave me instruction that it should be as I mentioned...

[flotus1]

I mentioned that the outcome of the tutorial would not be the kind of mesh you wanted, but an alternative with better mesh quality.

Tell your supervisor that the type of mesh he suggests will produce cells with bad quality in the center of the pipe (low angle to be more precise). Fluent WILL have trouble dealing with such cells, resulting in poor convergence or even divergence.
Honestly, I cant think of a reason to use the mesh type your supervisor suggested other than showing that Fluent cant handle it very well.

[ghost82]

Best mesh is what flotus recommended and what you drew in your last message.
I don't know how to use ansys meshing but you can add a boundary layer on wall to improve the mesh.
Moreover, in your first picture, the transition in size from the boundary layer to the center is too big in my opinon: transition in size should be 20-30% of adjacent cell.

[ghost82]

If you want for some reasons draw the mesh of the first post you can search if there is the equivalent of gambit of the " Quad/Tri:Wedge Primitive meshing scheme".
Or that mesh can be drawn easely in gambit by splitting the circle into another smaller circle at the center and meshing it by tri elements and use quad mesh for the outer portion.

[Coatilque]

I understand what You mean about problem with mesh in centre of circle
(sth like this pink pipe here: http://www.cfd-online.com/Forums/ans...wing-pipe.html)
I was thinking about sth like this one: http://www.cfd-online.com/Forums/ans...amic-mesh.html


Ok. More or less, I know what kind of analysis I should do.

Analysis of vertical pipe below;
Dimensions:
height: 20 [m]
diameter: 50 mm


How type of mesh You recommend for this? Multi zone + inflation?

[zhouxman]

May be the Gambit is a good option

you can divide the section

[somia baali]

hello i want to do like your mesh but i don't know how
would you show me step by step how you did it please
thank you