An impeller for a pump for conveying wastewater is proposed, includes a shroud to be rotated about an axis of rotation defining an axial direction, and a blade to convey the wastewater. The blade includes a leading edge, a trailing edge, a pressure side, a suction side and an upper rim. The blade extends from the shroud in the axial direction to the upper rim and extends in a circumferential direction from the leading edge to the trailing edge. The suction side is the radially inner surface of the blade and the pressure side is the radially outer surface of the blade. The blade includes a closed passage extending inside the blade. The passage has an inlet at the pressure side and an outlet at the suction side of the blade.

An improved centrifugal pump uses straight tubes or fluid channel members rather than expanding passages between the inlet and exit flow. In straight tubes a process occurs of building up of pressure faster than within the passages as the fluid attempts to expand due to the Coriolis force potentially acting against the centrifugal force to build up the pressure within and along the tube or fluid channel. Because the flow increases faster than increases in RPM a more compact pump is provided that can move more air and produce higher pressures than ordinary centrifugal pumps. Hence: 1) Flow increases proportional to tube area because a larger area means more air can be drawn into the tube; 2) Flow increases proportional to tube length because the exit pressure increases proportional to tube length; and 3) Flow increases faster than increases in RPM, thereby exhibiting a higher outflow pressure.

A centrifugal pump with a rotor having at least one blade and a method for configuring the profile of a blade is provided. The blade has a profile which is obtained by superposing a symmetric profile with at least one additional profile and a camber line whose blade inlet angle is smaller than 0.

A fish-friendly centrifugal pump having an impeller. The impeller includes a base that is concentric relative to a rotational axis of the impeller and an impeller body formed as at least one oblique cone having an eccentric apex and a smooth outer surface. The at least one oblique cone extends from the base.

The invention relates to a spiral pump and a device for treating water comprising this spiral pump, and associated method. The spiral pump comprises: a housing provided with an inlet for water; and a pump body which is accommodated in the housing and rotatable around an axis, wherein the pump body comprises at least one spiral channel, wherein a first outer end of the at least one spiral channel is located on an outer side of the pump body and forms an entrance opening for alternately taking in water and air through rotation of the pump body in the housing, and a second outer end of the at least one spiral channel debouches into an outlet close to the axis, wherein the housing is embodied as pressure chamber and wherein the at least one channel is provided with an increasing diameter from the entrance openings in the direction of the axis.

An impeller for a pump for conveying wastewater is proposed, includes a shroud to be rotated about an axis of rotation defining an axial direction, and a blade to convey the wastewater. The blade includes a leading edge, a trailing edge, a pressure side, a suction side and an upper rim. The blade extends from the shroud in the axial direction to the upper rim and extends in a circumferential direction from the leading edge to the trailing edge. The suction side is the radially inner surface of the blade and the pressure side is the radially outer surface of the blade. The blade includes a closed passage extending inside the blade. The passage has an inlet at the pressure side and an outlet at the suction side of the blade.