Learning Forum

[S.M. Naqib-Ul-Islam]

I am a new user. Currently I am doing a simulation on helical pipe using Fluent. As far as I know; when element size is reduced, element numbers should increase. But in my case it doesn't change much or when I am reducing the size the element numbers are sometimes increasing and sometimes decreasing.

How can I solve this problem? And how can I make the mesh finer?

[Keyur Kanade]

It all depends on what sizing function you are using. It also depends on different parameters you are using like angle - in case of curvature sizing, no. of elements in gap - in case of proximity sizing etc. 

Please check following link. 

Sizing Group (ansys.com)

 

Please go through help manual for more details 

Regards,

Keyur

How to access Ansys Online Help Document

Guidelines on the Student Community

Fluids Engineering Courses | Ansys Innovation Courses

 

[NickFL]

You could make a blocking structure that could be used to multiple geometries. Even if the pitch or radius changed, the number of mesh elements would be the same. It could even be copied to allow for additional turns. This would then allow you to put a fixed number of divisions on each edge of the blocking and know even before you created the mesh how many elements you would have.

BUT...if you start deviating too drastically from design to design, then the mesh quality can go kaputt. For instance, if you doubled the pitch size the aspect ratio is effectively doubled in addition to the skewness and other mesh quality statistics worsening. So, as always, there is a trade-off to such things.