The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 03, 2000
Filed:
Nov. 23, 1998
Alexander Bock, Zossen, DE;
Rolls-Royce Deutschland GmbH, Oberursel, DE;
Abstract
A passive clearance control system is provided in the turbine section of a gas turbine engine in which turbine casing nozzle vanes and rotor blades are provided. The rotor blades are arranged on a rotor and preferably fitted with a shroud. The tips of the blades or shroud are surrounded by shroud segments suspended in the turbine casing, and a clearance between the tips and the shroud segments is formed and has a width which is controlled by a heating-cooling channel system. The channel system is supplied with a stream of air from the compressor section of the gas turbine and bypasses the combustion chamber to reach, via a plurality of metering holes, an annulus bounded by a stator ring. In a preferred aspect of the present invention, a ring-shaped orifice plate interacting with the metering holes is provided within the annulus which closes these metering holes to a varying degree depending on the temperature of the air stream reaching the heating-cooling channel system. A fraction of the hot gas flowing across the nozzle vanes and rotor blades is allowed to reach the annulus via a clearance between the stator ring and the stator shroud segments at least at a low turbine load.