| 摘要 |
PROBLEM TO BE SOLVED: To solve a conventional problem relating to excessive gap wear at the front end of a turbine blade in a gas turbine engine, which occurs during transition from an idling speed to a high speed or to high-speed operation. SOLUTION: The gap 18 between the front end of the movable blade 16 of the turbine rotor in the gas turbine engine and a turbine ring 22 of an external casing encircling the blade is increased with a temporary increase in the inner diameter of the turbine ring each time when a turbomachine is operated at an idling speed or a high speed. The wear at the front end of the blade due to the contact with the turbine ring is avoided or minimized during transition from the idling speed to a higher speed or high-speed operation. The gap is increased by heating the external casing, specifically, by electrically heating at least one resistance circuit 30 held by the external casing. COPYRIGHT: (C)2007,JPO&INPIT |
