| 摘要 |
A means for forming a fluid-contacting surface on such as a stationary deflector or a blade (1), of a rotatable impeller or propeller, and any device incorporating or provided with such fluid-contacting surface, wherein said surface comprises at least part of the surface generated by a generating line (OP) extending radiallv from a point of origin (O), on a axis (Z), and rotated about said axis from said point and radial position so as to sweep through a decreasing |
