Pump impeller

An open-vane impeller for a regenerative turbine pump comprising:

• a hub having a cylindrical outer ring centered on a rotational axis of said impeller and bounded on a first side by an a first end wall in a first plane perpendicular to said rotational axis and on a second side by a second end wall in a second plane perpendicular to said rotational axis,
• means defining a first stage of open-vane impeller vanes on said cylindrical outer ring extending radially out therefrom with a longitudinally outboard edge of each of said open-vane impeller vanes in said first stage disposed in said first plane and a longitudinally inboard edge disposed in a third plane perpendicular to said rotational axis between said first and said second planes, and
• means defining a second stage of open-vane impeller vanes on said cylindrical outer ring extending radially out therefrom in side-by-side and phase shifted relationship to said first stage of open-vane impeller vanes,
• each of said open-vane impeller vanes in said second stage having a longitudinally outboard edge disposed in said second plane and a longitudinally inboard edge disposed in said third plane.