Abstract: A multistage radial compressor (1) with at least two compressor stages for compressing a fluid has a compressor housing (16) in which a flow channel (2) is formed for the fluid to be compressed; an impeller (4) with a plurality of impeller vanes (5) which are arranged in the flow channel (2) and are rotatable with the impeller (4) around a driveshaft (A), and a 3D return blading (8) with a plurality of return vanes (9) which are fixed with respect to rotation relative to the compressor housing (16). The flow channel (2) has a curved deflecting channel (7) which is arranged in front of the return vanes (9) in the flow direction. A vane base (11) and/or, axially downstream thereof, a vane head (12) of the return vanes (9) of the 3D return blading (8) have/has a curvature, and/or the return vanes (9) have a first vane angle distribution (17) at the vane base (11) and a second vane angle distribution (18) differing from this at the vane head (12).

Abstract: A multistage radial compressor (1) with at least two compressor stages for compressing a fluid has a compressor housing (16) in which a flow channel (2) is formed for the fluid to be compressed; an impeller (4) with a plurality of impeller vanes (5) which are arranged in the flow channel (2) and are rotatable with the impeller (4) around a driveshaft (A), and a 3D return blading (8) with a plurality of return vanes (9) which are fixed with respect to rotation relative to the compressor housing (16). The flow channel (2) has a curved deflecting channel (7) which is arranged in front of the return vanes (9) in the flow direction. A vane base (11) and/or, axially downstream thereof, a vane head (12) of the return vanes (9) of the 3D return blading (8) have/has a curvature, and/or the return vanes (9) have a first vane angle distribution (17) at the vane base (11) and a second vane angle distribution (18) differing from this at the vane head (12).

Abstract: A spiral housing with a spiral cross-section for a turbomachine, in which a disk diffuser with an upstream annular disk space is asymmetrical to the spiral cross-section. This spiral cross-section has a base circle of substantially constant diameter. The spiral cross-section also has a tongue region and a region adjacent to the tongue with circular spiral cross-sections extending to where an outside diameter of the spiral cross-section equals a specific diameter and the circular spiral cross-sections continue thereafter to increase in cross-section only axially.