Trouble with Generating a Structured Block for a Circular Nozzle
 

Hi

I want to create a structured block for my circular nozzle as a part of the free jet analysis I wish to perform in Ansys CFX. I created the domain in the circular surfaces in 2 ways. The first time I used a Pole to create a circular mesh and in the second time I tried using the butterfly topology as mentioned in Pointwise Tutorials. The mesh gets created and desired skewness is maintained.

I am unable to convert the domains into a block. Documentation says I need 6 faces to created a structured block. So I split the circular faces into 2 parts to get 6 faces, but it does not let me choose the 6th face. I receive the error "Cannot create block with chosen surfaces" I have attached a pic of the same. Please do help me out.