I am currently using ANSYS Fluent in meshing mode and am having trouble applying the size functions. I currently have two cylinders, one much smaller and completely within the other. I set up a size function for the smaller cylinder that should cause the volume mesh within it to be much smaller than the surrounding mesh in the larger cylinder. I set the size function using the BOI setting. However, when i use AutoMesh to create the hexcore volume mesh, I simply receive large hexahedral cells throughout the entire meshing region without any extra refinement in the smaller cylinder. By chance do you know what might be causing this problem? Do you need any further information?