autogrid problem in defining semi-open imepller
 

I want to define a semi-open (unshrouded) impeller in autogrid 5 but it errors that "leading edge does not intersect shroud",
when I add a shroud gap to a shrouded impeller(closed impeller) I think it would not be the same as what I want because of intersection of shroud and impeller in two edges, please help me!:confused: