When Float leading and trailing edge vertices on blade is enabled, a folded mesh can be obtained for high twisted blades.
Parameterization of two surfaces adjacent to leading or trailing edge may not have the same parameterization from hub to shroud.
Suing streamwise lofting of blade or
Mesh Generation parameter set to Constant Span or
Moving the leading and trailing points (geometry) and mesh with Float leading and trailing edge vertices on blade disabled
ANSYS CFX Release 11.0 Update 1.