# US 2006/0222486 A1 · Cooling system for a gas turbine engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2006/0222486 A1 - Document ID: US20060222486A1 - Status: Published application - Kind: A1 - Application number: 11/385,645 - Filed: 2006-03-22 - Published: 2006-10-05 - Earliest claimed: 2005-04-01 - Assignees: ROLLS-ROYCE plc - Inventors: Alan Maguire; John Hoptroff - Web page: https://patentgrep.com/patent/US20060222486A1 ## CPC - F01D 5/081: {Cooling fluid being directed on the side of the rotor disc or at the roots of the blades (F01D5/087 takes precedence)} - F01D 11/001: {for sealing space between stator blade and rotor} - F05D 2250/314: the axes being inclined in relation to each other - F05D 2260/601: using an ejector or a jet pump - 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 cooling system for a gas turbine engine (FIG. 1) comprises a pre-swirl arrangement, preferably including a pre-swirl chamber, for providing cooling air to a turbine blade disc, and a ventilation arrangement for providing ventilation air to a rotating component of the gas turbine engine. The cooling system includes an air bypass arrangement, which preferably includes first, second and third air bypass duct portions, for conveying ventilation air away from the pre-swirl arrangement. ## Claims ### Claim 1 A cooling system for a gas turbine engine, the cooling system comprising a pre-swirl arrangement for providing cooling air to a turbine blade disc, and a ventilation arrangement for providing ventilation air to a rotating component of the gas turbine engine, characterised in that the cooling system includes an air bypass arrangement for conveying ventilation air away from the pre-swirl arrangement. ### Claim 2 (depends on 1) A cooling system according to claim 1, wherein the air bypass arrangement is arranged to convey ventilation air to a further rotating component of the gas turbine engine to provide cooling to the further rotating component. ### Claim 3 (depends on 1) A cooling system according to claim 1, wherein the air bypass arrangement includes an air bypass duct for conveying ventilation air to a further rotating component of the gas turbine engine to provide cooling to the further rotating component. ### Claim 4 (depends on 3) A cooling system according to claim 3, wherein the air bypass duct includes a first air bypass duct portion extending circumferentially about a rotational axis of the gas turbine engine. ### Claim 5 (depends on 4) A cooling system according to claim 4, wherein the first air bypass duct portion is generally annular. ### Claim 6 (depends on 4) A cooling system according to claim 4, wherein the first air bypass duct portion defines an air inlet for receiving, in use, ventilation air from the ventilation arrangement. ### Claim 7 (depends on 6) A cooling system according to claim 6, wherein the air inlet is also arranged to receive, in use, a proportion of cooling air from the pre-swirl arrangement. ### Claim 8 (depends on 1) A cooling system according to claim 1, wherein the air bypass arrangement includes a second air bypass duct portion which intersects the pre-swirl arrangement. ### Claim 9 (depends on 8) A cooling system according to claim 8, wherein the second air bypass duct portion intersects an air supply arrangement of the pre-swirl arrangement. ### Claim 10 (depends on 9) A cooling system according to claim 9, wherein the second air bypass duct portion extends generally radially through the air supply arrangement. ### Claim 11 (depends on 1) A cooling system according to claim 1, wherein the air bypass arrangement includes a third air bypass duct portion defined in part by a static component of the gas turbine engine structure. ### Claim 12 (depends on 11) A cooling system according to claim 11, wherein the third air bypass duct portion is defined in part by a combustion rear inner casing of the gas turbine engine. ### Claim 13 (depends on 11) A cooling system according to claim 11, wherein the third air bypass duct portion is further defined in part by a movable sealing component of the gas turbine engine. ### Claim 14 (depends on 13) A cooling system according to claim 13, wherein the third air bypass duct portion is further defined in part by an expandable sealing member provided between the movable sealing component and the pre-swirl arrangement. ### Claim 15 (depends on 14) A cooling system according to claim 14, wherein the expandable sealing member is operable in use to prevent the passage of cooling air from the pre-swirl arrangement into the third air bypass duct portion. ### Claim 16 (depends on 14) A cooling system according to claim 14, wherein the expandable sealing member comprises a spiral sealing ring arrangement. ### Claim 17 (depends on 23) A cooling system according to claim 23, wherein the second air bypass duct portion is arranged to receive air from the first air bypass duct portion and to convey the air into the third air bypass duct portion. ### Claim 18 (depends on 13) A cooling system according to claim 13, wherein the movable sealing component includes a pre-swirl means and the third air bypass duct portion is arranged to convey the air from the third air bypass duct portion through the pre-swirl means. ### Claim 19 (depends on 18) A cooling system according to claim 18, wherein the pre-swirl means is arranged to convey air from the third air bypass duct portion towards a rotating seal component of the gas turbine engine to cool the rotating seal component. ### Claim 20 (depends on 18) A cooling system according to claim 18, wherein the pre-swirl means is arranged to convey air from the third air bypass duct portion towards a rim of the turbine blade mounting disc to cool the disc rim. ### Claim 21 (depends on 18) A cooling system according to claim 18, wherein the pre-swirl means is arranged to convey air from the third air bypass duct portion into a cooling passage of a turbine blade to cool the blade. ### Claim 22 (depends on 1) A gas turbine engine including a cooling system according to claim 1. ### Claim 23 (depends on 4) A cooling system according to claim 4, wherein the air bypass arrangement includes a second air bypass duct portion which intersects the pre-swirl arrangement.