초록

A compressor bleed valve system for bleeding air from a gas turbine engine compressor comprises a bladder inflatable between at least a collapsed position and an expanded position for selectively opening and closing a compressor airbleed passage.

대표청구항 ▼

1. A gas turbine engine comprising a main fluid flow path, a compressor forming a portion of said main fluid flow path, at least first and second passages for bleeding compressor air from said fluid flow path, and a compressor bleed valve system comprising a bladder inflatable between at least a col

1. A gas turbine engine comprising a main fluid flow path, a compressor forming a portion of said main fluid flow path, at least first and second passages for bleeding compressor air from said fluid flow path, and a compressor bleed valve system comprising a bladder inflatable between at least a collapsed position and an expanded position for controlling a flow of compressor air from said main fluid flow path through said at least first and second passages, said bladder including at least two inflatable segments selectively inflatable relative to one another for controlling fluid flow through a respective one of said first and second passages.2. A gas turbine engine am defined in claim 1, wherein said at least first and second passages are at least partly opened when the bladder is deflated to said collapsed position thereof, and wherein said at least first and second passages are closed when said bladder is inflated to said expanded position thereof.3. A gas turbine engine as defined in claim 2, wherein said bladder acts as an inflatable seal to sealingly close said at least first and second passages when inflated to said expanded position.4. A gas turbine engine as defined in claim 3, wherein said at least first and second passages includes a plurality of spaced-apart passages, and wherein said bladder simultaneously seals at least two of said plurality of spaced-apart passages, when inflated to said expanded position.5. A gas turbine engine as defined in claim 4, wherein said plurality of passages includes first and second series of passages, inflatable segments, each sealing a respective ones of said first and second series of passages.6. A gas turbine engine as defined in claim 4, wherein said plurality of spaced-apart passages includes a row of circumferentially distributed passages, and wherein said bladder is positioned radially outwardly of said row of circumferentially distributed passages, said bladder being expandable radially inwardly towards said row of passages for controlling the flow of compressor air therethrough.7. A gas turbine engine as defined in claim 6, wherein said least two inflatable segments are circumferentially oppositely disposed relative to one another.8. A gas turbine engine as defined in claim 6, wherein said bladder is expandable radially inwardly from a support ring mounted between a by-pass flow path and said main fluid flow path.9. A gas turbine engine as defined in claim 1, wherein said at least two inflatable segments are in fluid flow communication with a source of fluid pressure via a control valve, said control valve being displaceable between at least a first position wherein both said inflatable segments are connected in fluid flow communication with said source of fluid pressure and a second position wherein only a selected one of said inflatable segments is connected in fluid flow communication with said source of fluid pressure.10. A gas turbine engine as defined in claim 1, wherein said at least two inflatable segments cooperate to form a circumferentially extending boot positioned about said main flow path, said boot being expandable radially inwardly to sealingly cover said at least first and second passages.11. A combination compressor bleed valve actuation and seal system for bleeding air from a gas turbine engine compressor, wherein the gas turbine engine compressor has at least two airbleed passages; the system comprising: a seal including at least first and second boot segments independently inflatable for selectively opening and closing respective ones of the at least two airbleed passages.12. A combination as defined in claim 11, wherein said seal is mounted to a circumferentially extending seal carrier, said seal projecting radially inwardly of said seal carrier when inflated to said expanded position.13. A combination as defined in claim 11, wherein said first and second inflatable boot segments extend in circumferential opposite directions about said at least one airbleed passage.14. A combination as defined in claim 11, wherein said first and second boot segments are in fluid flow communication with a source of fluid pressure via a control valve, said control valve being displaceable between at least a first position wherein both said first and second boot segments are connected in fluid flow communication with said source of fluid pressure and a second position wherein only a selected one of said boot segments is connected in fluid flow communication with said source of fluid pressure.15. A combination compressor bleed valve actuation and seal system for bleeding air from a gas turbine engine compressor, wherein the gas turbine engine compressor has at least two airbleed passages; the system comprising a bladder including first and second boot segments separately inflatable between at least a collapsed position and an expanded position for selectively opening and closing respective ones of said at least two airbleed passages.16. A combination as defined in claim 15, wherein said bladder acts as an inflatable seal to sealingly close said at least one passage when inflated to said expanded position.17. A combination as defined in claim 16, wherein said inflatable seal is mounted to a circumferentially extending seal carrier, said seal projecting radially inwardly of said seal carrier when inflated to said expanded position.18. A combination as defined in claim 15, wherein said first and second inflatable boot segments extend in circumferential opposite directions about said at least two airbleed passages.19. A combination as defined in claim 15, wherein said first and second boot segments are in fluid flow communication with a source of fluid pressure via a control valve, said control valve being displaceable between at least a first position wherein both said first and second segments are connected in fluid flow communication with said source of fluid pressure and a second position wherein only a selected one of said boot segments is connected in fluid flow communication with said source of fluid pressure.20. A method of bleeding air from a gas turbine engine compressor, the compressor including a main air flow path in communication with a plurality of bleed passages, the method comprising the steps of: a) providing an inflatable member having at least first and second separately inflatable boot segments, each segment defining a pressurizable chamber, and b) selectively varying an internal fluid pressure of said pressurizable chamber of said separately inflatable boot segments to control an air flow from said main air flow path through said bleed passages.21. A method as defined in claim 20, wherein step b) comprises the step of inflating least a selected one of said boot segments to an expanded position wherein said least selected one of said boot segments substantially sealingly closes at least some of, said bleed passages.22. A method as defined in claim 21, wherein said first and second boot segments, each cover a series of bleed passages, and wherein step b) further comprises the steps of selecting the series of bleed passages to be closed and inflating at least one of said first and second boot segments in accordance with the selected series of bleed passages.23. A method as defined in claim 20, wherein said inflatable member includes a sealing boot extending about said main air flow path, and wherein step b) comprises the steps of expanding said sealing boot radially inwardly towards said bleed passages in order to incrementally limit the flow of air passing from said main air flow path through said bleed passages.