Patent ID: 8721273

Claim:
An arrangement for an axial turbomachine, comprising: a ring-shaped flow duct which is delimited by a first wall surface and a second wall surface of an outer wall and of an inner wall, respectively, and between which is provided a guide vane cascade through which a medium is capable of flowing; the guide vane cascade, comprising, a plurality of aerodynamically curved vane leaves, the free-standing vane leaf tips of which lie, radially on the inside, opposite the inner wall of the flow duct or, radially on the outside, opposite the outer wall of the flow duct, in each case so as to form a gap; and a ring diffuser arranged downstream of the guide vane cascade, with a ring diffuser outer wall and with a ring diffuser inner wall coaxial with the ring diffuser outer wall, between which a diffuser duct extends in ring form along an axial extent so as to diverge from an inflow-side end to an outflow-side end, wherein the ring diffuser inner wall and the ring diffuser outer wall in each case comprising a second ring diffuser wall surface and a first ring diffuser wall surface, respectively, delimiting the diffuser duct, wherein the ring diffuser outer wall is arranged downstream of the outer wall of the flow duct and/or the ring diffuser inner wall is arranged downstream of the inner wall of the flow duct, wherein the second ring diffuser wall surface of the ring diffuser inner wall and/or the first ring diffuser wall surface of the ring diffuser outer wall is rotationally asymmetrical at least in a first portion of the ring diffuser, wherein the second ring diffuser wall surface at which the gaps are arranged further upstream is a rotationally asymmetrical design, and wherein the first portion is arranged at the inflow-side end of the ring diffuser and merges into a rotationally symmetrical second portion which is arranged downstream of the rotationally asymmetrical first portion in relation to the throughflow direction of the ring diffuser.