Abstract: A radial expander having a rotor mounted in a housing and comprising multiple blades. The blades together with a radially inner hub contour of a rotor hub and a radially outer housing contour define flow channels for the process gas, which process gas to be expanded enters in a radial direction and from which expanded process gas exits in the axial direction. The radially inner hub contour of the rotor includes a curvature change at least in some circumferential positions seen in the meridional section such that adjacent to a flow leading side of the rotor, the radially inner hub contour, seen in the meridional section, is curved radially to the outside and adjacent to a flow trailing side of the rotor, the radially inner hub contour, seen in the meridional section, is curved radially to the inside.

Abstract: A radial expander having a rotor mounted in a housing and comprising multiple blades. The blades together with a radially inner hub contour of a rotor hub and a radially outer housing contour define flow channels for the process gas, which process gas to be expanded enters in a radial direction and from which expanded process gas exits in the axial direction. The radially inner hub contour of the rotor includes a curvature change at least in some circumferential positions seen in the meridional section such that adjacent to a flow leading side of the rotor, the radially inner hub contour, seen in the meridional section, is curved radially to the outside and adjacent to a flow trailing side of the rotor, the radially inner hub contour, seen in the meridional section, is curved radially to the inside.