Hello I am not very familiar with meshing geomytries specially 3D ones. I really appreciate if you provide some input.my geometry is a helical pipe(heat exchanger) wich circulate water inside it this pipe is buried in ground wich is considered as a cylinder domain,so i easly made my 3D geomtry using Gambit but i have no idea how to start meshing it to simulate heat transfer between pipe and ground.