Turbomachine for increasing the pressure of a fluid or mixture of fluids, comprising an inlet and an outlet, a casing, a rotatable shaft arranged in the casing, diffusers or similar operatively arranged in the turbomachine, and a means for rotation operatively connected to the shaft. The turbomachine is distinguished in that it comprises: at least one
impeller of a
mixed flow type arranged on the shaft, the
impeller having an inlet and an outlet, the inlet is closer to an axis of rotation than the outlet; and at least one further
impeller arranged on a common or operatively connected shaft, chosen from the group consisting of axial impellers arranged upstream of the
mixed flow type impeller and radial impellers arranged downstream of the
mixed flow type impeller.
Impeller for use in a turbomachine for increasing the pressure of a fluid or mixture of fluids, the impeller comprising at least one blade, distinguished in that it comprises at least one fluid passageway fluidly connecting the pressure side of the blade with the leeward side of the blade.