| 摘要 |
Disclosed is a method of controlling tip clearance of rotor blades from a surrounding casing in a gas turbine engine and an associated clearance control system. The method comprises the steps of performing a first run of the gas turbine engine, shutting down the gas turbine engine and starting the gas turbine engine for a second run. At least one performance parameter, such as the air temperature in a cavity in the turbine engine, is measured during or after the first engine run but before air within the gas turbine engine, which is soaked to the approximate temperature of one or more surrounding engine components, is substantially displaced as a consequence of the second run. The thermal condition of at least part of the engine in accordance with the measured performance parameters is then recorded. Finally the recorded thermal condition is retrieved and the temperature of the casing is controlled during at least part of the second run in a manner dependent on it. The method allows for the air temperature used to control the diameter of the engine casing to take in to account any residual heat in the engine from a previous engine run. |
