Dear all,

I want to do simulation of internally grooved tube. I am using Ansys FLUENT 17.2. I have tried to make mesh by using ANSYS Meshing but it only generates tetra mesh. I want to make mesh like the attached figure by using ICEM CFD 17.2. But, I dont know how to do that. I am beginner in ICEM CFD. The  hex core in the center of the tube and Pyramids, tetrahedrons and prism on the near of the wall. Is ther any suggestion? Thank you