Is the use of "But with regard to" in the following sentences correct grammatically and conceptually? If it is not , kindly suggest ways to make it clearer.
As revealed in Ref. , twisted blades affect turbine performance significantly. But with regard to the twist in the blade profile of Wells turbine, the blade profile cannot be twisted because the angle of attack will be different in different flow directions and this causes big separation and low performance in one of the flow directions.