i have this question, as we know we make use of "rotating region" for bodies that rotate at certain RPM we use the same while working on a pump impeller also. We create a solid circular body around the impeller and say it rotates at 'X' RPM. But does this take into effect the blade shape and profile?. Because this can be one of the critical factor in pump design. What should be done if I have to look at the change in the flow parameters by change of blade profile. Thanka.