Abstract: An exhaust gas diffuser for a gas turbine is provided. The diffuser has an annular outer wall for guiding the diffuser flow and in which an annular guiding element is arranged concentrically to the outer wall and influences the diffuser flow. The guiding element has a surface which is radially directed inwards and has a circumferential contour that is convex in the longitudinal section to form a displacement element. The guiding element is axially displaceable between two positions so that the guiding element, when in a first position, allows a flow between the guiding element and outer wall and, when in a second position, largely prohibits a flow between the guiding element and outer wall. The aerodynamic effect of the diffuser is improved and simultaneously optimal adapted for a plurality of operational gas turbine states.

Abstract: An exhaust gas diffuser for a gas turbine includes a flow duct which widens towards a diffuser outlet. The flow duct includes an axially extending guide body, wherein the guide body, at least in an axial section of its longitudinal extent, has a plurality of recesses which are distributed over the circumference and arranged between guide elements. Each guide element extends along a spiral line along the longitudinal extent of the guide body. Further, a gas turbine plant with such an exhaust gas diffuser is provided.

Abstract: An exhaust gas diffuser for a gas turbine is provided. The diffuser has an annular outer wall for guiding the diffuser flow and in which an annular guiding element is arranged concentrically to the outer wall and influences the diffuser flow. The guiding element has a surface which is radially directed inwards and has a circumferential contour that is convex in the longitudinal section to form a displacement element. The guiding element is axially displaceable between two positions so that the guiding element, when in a first position, allows a flow between the guiding element and outer wall and, when in a second position, largely prohibits a flow between the guiding element and outer wall. The aerodynamic effect of the diffuser is improved and simultaneously optimal adapted for a plurality of operational gas turbine states.

Abstract: A diffuser arrangement through which a fluid may flow is provided. The diffuser includes an outer diffuser comprising an inner surface, and a flow-guiding device, which is configured such that at least part of the boundary layer flow forming on the inner surface of the outer diffuser can be accelerated in the main flow direction, so that a flow separation is prevented on the inner surface of the outer diffuser. Also provided are an exhaust steam plenum of a steam turbine and an exhaust gas plenum of a gas turbine, both including a diffuser arrangement.