hexa mesh for turbines using ICEM
 

Can I get an idea on the meshing techniques for this runner http://www.ltu.se/cms_fs/1.111520!/file/Runner.zip

In that geometry Mesh already prepared and included.
(1) Open Geometry in ICEM *.tin file
(2) Import block file *.blk
(3) Create pre-mesh.
(4) Convert to unstructured

For You must have knowledge about ICEM CFD Blocking technique.

I wanted to know on how they have done it, especially the blocking of the turbine.
Any ideas on how to recreate the same mesh with the geometry file.

Then You have to learn blocking techniques. You may start from the tutorial available in ICEM CFD. The blocking can be performed any type of geometry just you have to explore the decomposition technique using available commands.