hello,everyone, I have a question about merge mesh. I want to merge two mesh (hexa and tetra). Before merge I have checked the grid quality of hexa and tetra, not bad,hexa is 0.4, tetra is o.25. but after merge mesh ,the grid quality is very low, the grids with low quality are the pyramid grids on interface, who can tell me,how to solve this problem?? how to improve the quality of pyramid grids after merge mesh ?? (I have used the smooth mesh option,but it is not work ) thanks for answer .

It could be helpful if you tell us which software you are using.

sorry, I forget to say, I use ICEM

Best to make the quads and tris on the boundary as close to the same size as possible (edge lengths). That usually provides a less-skewed pyramid. You can also smooth after-the-fact. (But freeze the hex elements.)