Patent attributes
A mixed-flow turbine wheel is proposed which, compared to existing mixed-flow turbine wheels, has reduced mass and moment of inertia because radially-outer portions of existing mixed-flow turbine wheels are omitted. In a first possibility, the omitted material may be scalloping of the back face of the turbine wheel at a radial position outward of a base line which is a circle on the back surface of the wheel which indicates the minimum radius of the back surface. In a second possibility, part of the webbing of each blade is omitted to one side of the blade. Thus, viewing the turbine wheel in the axial direction, the area of the webbing outside the baseline and to one side of a radial line through the inducer tip, may be at least 20% less than that on the other side.