Reply To: How to make my simulation converge?

[Tomomi]

Hi Rob, Thank you very much for your detailed advice. I deeply appreciate your help.

I watched the video for BOI and was trying to adopt BOI, but I couldn't find the same one in Ansys Fluent Meshing. When making mesh, I always use Ansys Fluent Meshing. In terms of functions, is BOI in Design Modeler similar to Local Meshing in Ansys Fluent Meshing? Which do you recommend me to use for meshing, Design Modeler or Ansys Fluent Meshing? 

So, before removing the metal and adopting BOI, for the first simple attempt, I tried to improve my mesh by changing the mesh size and mesh shape. But it didn't work. The screenshots of the mesh and the velocity contour are below. 

When looking at the meshes, I thought that this mesh was better than the previous one, but the result said that the mesh quality got worse (Minimum Orthogonal Quality = 0.05, Maximum skewness = 0.43). I couldn't understand why. Is this mesh not good enough to analyze the flow in this pipe? 

I apologize for disturbing you with so many basic questions, but I would appreciate it if you could give me some suggestions.