# US 2014/0154061 A1 · Turbine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0154061 A1 - Document ID: US20140154061A1 - Status: Published application - Kind: A1 - Application number: 14/235,198 - Filed: 2012-09-18 - Published: 2014-06-05 - Earliest claimed: 2011-09-20 - Assignees: Mitsubishi Heavy Industries, Ltd. - Applicants: Mitsubishi Heavy Industries, Ltd. - Inventors: Yoshihiro Kuwamura; Kazuyuki Matsumoto; Hiroharu Oyama; Yoshinori Tanaka; Asaharu Matsuo - Web page: https://patentgrep.com/patent/US20140154061A1 ## CPC - F01D 11/08: for sealing space between rotor blade tips and stator (specially-shaped blade tips therefor F01D5/20) - F01D 5/225: {by shrouding} - F01D 11/001: {for sealing space between stator blade and rotor} - F01D 11/02: by non-contact sealings, e.g. of labyrinth type (for sealing space between rotor blade tips and stator F01D11/08) - F05D 2250/182: crenellated, notched - 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 Provided is a turbine. One of a tip portion of a blade and a portion of a partition plate outer ring corresponding to the tip portion of the blade is provided with a step part having a step face that protrudes toward the other, and the other is provided with seal fins) extending out with respect to the step part and forming minute clearance between the step part and the other. The step part facing the seal fins is configured to protrude so that a cavity forming a main vortex and counter vortex being formed by the main vortex are formed on an upstream side of the seal fins. The cavity is formed so that an axial width dimension and a radial height dimension satisfy Formula expressed by 0.45≦D/W≦2.67. ## Claims ### Claim 1 A turbine comprising: a blade; and a structure being provided in a tip portion of the blade with a gap and which configured to rotate relatively shaft axis relative to the blade, wherein one of the tip portion of the blade and a portion of the structure corresponding to the tip portion of the blade is provided with a step part having a step face that protrudes toward the other, the other is provided with seal fins extending out with respect to the step part and forming minute clearance (H) between the step part and the other, the step part facing the seal fins is configured to protrude so that a cavity forming a main vortex and counter vortex being formed by the main vortex are formed on an upstream side of the seal fins, and the cavity is formed so that an axial width dimension (W) and a radial height dimension (D) satisfy Formula (1) below. 0.45≦D/W≦2.67 (1) ### Claim 2 (depends on 1) The turbine according to claim 1, wherein the cavity is formed so that an axial width dimension (W) and a radial height dimension (D) satisfy Formula (2) below. 0.56≦D/W≦1.95 (2) ### Claim 3 (depends on 1) The turbine according to claim 1, wherein the cavity is formed so that an axial width dimension (W) and a radial height dimension (D) satisfy Formula (3) below. 0.69≦D/W≦1.25 (3) ### Claim 4 (depends on 1) The turbine according to claim 1, wherein the minute clearance (H) and distances (L) between the seal fins and end edges of the step part which is located on the upstream side of the step part are formed to satisfy Formula (4) below with respect to at least one of the distances (L). 0.7H≦L≦0.3W (4) ### Claim 5 (depends on 1) The turbine according to claim 1, wherein the minute clearance (H) and distances (L) between the seal fins and end edges of the step part which are located on the upstream side of the step part are formed to satisfy Formula (5) below with respect to at least one of the distances (L). 1.25H≦L≦2.75H (where L≦0.3W) (5) ### Claim 6 (depends on 2) The turbine according to claim 2, wherein the minute clearance (H) and distances (L) between the seal fins and end edges of the step part which is located on the upstream side of the step part are formed to satisfy Formula (4) below with respect to at least one of the distances (L). 0.7H≦L≦0.3W (4) ### Claim 7 (depends on 3) The turbine according to claim 3, wherein the minute clearance (H) and distances (L) between the seal fins and end edges of the step part which is located on the upstream side of the step part are formed to satisfy Formula (4) below with respect to at least one of the distances (L). 0.7H≦L≦0.3W (4) ### Claim 8 (depends on 2) The turbine according to claim 2, wherein the minute clearance (H) and distances (L) between the seal fins and end edges of the step part which are located on the upstream side of the step part are formed to satisfy Formula (5) below with respect to at least one of the distances (L). 1.25H≦L≦2.75H (where L≦0.3W) (5) ### Claim 9 (depends on 3) The turbine according to claim 3, wherein the minute clearance (H) and distances (L) between the seal fins and end edges of the step part which are located on the upstream side of the step part are formed to satisfy Formula (5) below with respect to at least one of the distances (L). 1.25H≦L≦2.75H (where L≦0.3W) (5) ### Claim 10 (depends on 4) The turbine according to claim 4, wherein the minute clearance (H) and distances (L) between the seal fins and end edges of the step part which are located on the upstream side of the step part are formed to satisfy Formula (5) below with respect to at least one of the distances (L). 1.25H≦L≦2.75H (where L≦0.3W) (5) ### Claim 11 (depends on 6) The turbine according to claim 6, wherein the minute clearance (H) and distances (L) between the seal fins and end edges of the step part which are located on the upstream side of the step part are formed to satisfy Formula (5) below with respect to at least one of the distances (L). 1.25H≦L≦2.75H (where L≦0.3W) (5) ### Claim 12 (depends on 7) The turbine according to claim 7, wherein the minute clearance (H) and distances (L) between the seal fins and end edges of the step part which are located on the upstream side of the step part are formed to satisfy Formula (5) below with respect to at least one of the distances (L). 1.25H≦L≦2.75H (where L≦0.3W) (5)