# US 12,180,849 B1 · Mitigation of rotating stall in turbine exhaust section using flow control vanes disposed therein > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,180,849 B1 - Document ID: US12180849B1 - Status: Granted - Kind: B1 - Application number: 18/395,326 - Filed: 2023-12-22 - Granted: 2024-12-31 - Earliest claimed: 2023-12-22 - Assignees: GE Infrastructure Technology LLC - Applicants: GE Infrastructure Technology LLC - Inventors: Shashwat Swami Jaiswal; Moorthi Subramaniyan; Gunnar Leif Dan Siden; Nisha Singh - Web page: https://patentgrep.com/patent/US12180849B1 ## CPC - F01D 17/167: {of vanes moving in translation} - F01D 5/141: {Shape, i.e. outer, aerodynamic form (F01D5/148 - F01D5/20 take precedence; blade construction F01D5/147)} - F01D 17/143: {the shiftable member being a wall, or part thereof of a radial diffuser} - F01D 25/30: Exhaust heads, chambers, or the like - F05D 2250/70: Shape - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract A system includes a turbine exhaust section having an exhaust flow path, an inner exhaust wall radially disposed along the exhaust flow path, an outer exhaust wall disposed radially outward of the inner exhaust wall and along the exhaust flow path, and a flow control vane extending between a first end and a second end. The first and second ends are circumferentially offset from one another. The flow control vane is configured to move between a retracted position along the outer exhaust wall and an extended position extending from the outer exhaust wall toward the inner exhaust wall. The second end is disposed radially inward from the first end while the flow control vane is disposed in the extended position. ## Claims ### Claim 1 A system, comprising: a turbine exhaust section comprising: an exhaust flow path; an inner exhaust wall radially disposed along the exhaust flow path; an outer exhaust wall disposed radially outward of the inner exhaust wall and along the exhaust flow path; and a flow control vane extending between a first end and a second end, wherein the first and second ends are circumferentially offset from one another, the flow control vane is configured to move between a retracted position along the outer exhaust wall and an extended position extending from the outer exhaust wall toward the inner exhaust wall, and the second end is disposed radially inward from the first end while the flow control vane is disposed in the extended position. ### Claim 2 (depends on 1) The system of claim 1, wherein the flow control vane is disposed downstream of a last stage blade of the turbine exhaust section and upstream of a diffuser strut of the turbine exhaust section. ### Claim 3 (depends on 1) The system of claim 1, wherein a first radial extent of the first end and a second radial extent of the second end are different from one another. ### Claim 4 (depends on 1) The system of claim 1, wherein the flow control vane comprises a curved wall, wherein the curved wall comprises a cross-section swept along a curve from the first end to the second end. ### Claim 5 (depends on 4) The system of claim 4, wherein the cross-section comprises: a radial portion extending in a radial direction of the turbine exhaust section; and an axial portion extending crosswise from an outer radial edge of the radial portion; wherein the axial portion extends in an upstream direction of the turbine exhaust section. ### Claim 6 (depends on 5) The system of claim 5, wherein a radial extent of the radial portion increases from the first end to the second end. ### Claim 7 (depends on 4) The system of claim 4, wherein the flow control vane is configured to circumferentially curve about a central longitudinal axis of the turbine exhaust section. ### Claim 8 (depends on 4) The system of claim 4, wherein the curved wall comprises: a first curve portion extending from the first end in a downstream direction of the turbine exhaust section; and a second curve portion extending from the first curve portion in an upstream direction of the turbine exhaust section. ### Claim 9 (depends on 8) The system of claim 8, wherein a first concave side of the first curve portion and a second concave side of the second curve portion face the upstream direction. ### Claim 10 (depends on 8) The system of claim 8, wherein a radius of curvature of the curved wall increases from the first end to the second end along a length of the curved wall. ### Claim 11 (depends on 10) The system of claim 10, wherein a tangent of the curved wall at the second end is directed in a radial direction of the turbine exhaust section or in a direction angled upstream from the radial direction when the flow control vane is in the extended position. ### Claim 12 A system, comprising: a turbine exhaust section comprising: an exhaust flow path; an inner exhaust wall radially disposed along the exhaust flow path; an outer exhaust wall radially disposed along the exhaust flow path radially outward of the inner exhaust wall; and a flow control vane extending between a first end and a second end, wherein the first and second ends are circumferentially offset from one another, the flow control vane is configured to move between a retracted position and an extended position, the flow control vane is disposed along one of the inner and outer exhaust walls in the retracted position, the flow control vane extends between the outer exhaust wall and the inner exhaust wall in the extended position, and the flow control vane extends radially between the first and second ends in the extended position. ### Claim 13 (depends on 12) The system of claim 12, wherein the flow control vane is configured to curve radially inward from the first end to the second end when the flow control vane is in the extended position. ### Claim 14 (depends on 13) The system of claim 13, wherein the turbine exhaust section comprises one or more actuators configured to: cause a translation of the flow control vane in a radial direction of the turbine exhaust section; cause a rotation of the second end relative to the first end; or both. ### Claim 15 (depends on 12) The system of claim 12, wherein the flow control vane is disposed downstream of a last stage blade of the system and upstream of a strut of the turbine exhaust section. ### Claim 16 (depends on 12) The system of claim 12, wherein a first radial extent of the first end and a second radial extent of the second end are different from one another. ### Claim 17 A system, comprising: a turbine exhaust section comprising: an exhaust flow path; an inner exhaust wall radially disposed along the exhaust flow path; an outer exhaust wall radially disposed along the exhaust flow path radially outward of the inner exhaust wall; and a flow control vane extending between a first end and a second end, wherein the first and second ends are circumferentially offset from one another, the flow control vane is configured to move between a retracted position and an extended position, the flow control vane is disposed along one of the inner and outer exhaust walls in the retracted position, the flow control vane extends between the outer exhaust wall and the inner exhaust wall in the extended position, and the flow control vane extends radially between the first and second ends in the extended position, and the flow control vane has a variable width between the first and second ends. ### Claim 18 (depends on 17) The system of claim 17, wherein a first radial extent of the first end and a second radial extent of the second end are different from one another. ### Claim 19 (depends on 17) The system of claim 17, wherein the flow control vane comprises a curved wall, wherein the curved wall comprises a cross-section swept along a curve from the first end to the second end. ### Claim 20 (depends on 19) The system of claim 19, wherein the cross-section comprises an L-shaped contour comprising: a radial portion extending in a radial direction of the turbine exhaust section; and an axial portion extending crosswise from an outer radial edge of the radial portion; wherein the axial portion extends in an upstream direction of the turbine exhaust section.