[Aysiyi]

hello , everyone ,i am meshing a volute in a comprssor ,the biggest challenge is how to mesh the volute tongue zone of the volute . i think of a method and tried it . here is my method :
1. first , i create the 2d surface block of the volute tongue zone . then 2d to 3d , converting the surface blocking to 3d .
2. i save the 3d block file of the volute tongue. i create the mapped block of the rest parts of the volute .
3 open the previous block file of the volute tongue . and merge it .
4 , merge the corresponding vertex at the interface of the two blocks
to improve the mesh quality , i need to make o-grid in the mapped blocks ,however , the icem tells an error . so my question is :
is my blocking wrong ?　
what is the better block strategy?

thank in advance!!