Gas turbine engine and a rotor for a gas turbine engine

• US 20070031249A1
• Filed: 07/25/2005
• Published: 02/08/2007
• Est. Priority Date: 03/27/1999
• Status: Active Grant

• Current Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Inventors: Jones, Alan
• Granted Patent: US 7,507,070 B2
• Time in Patent Office: Days
• US Class Current: 415/200
• CPC Class Codes: F01D 11/18 using stator or rotor components with predetermined thermal response, e.g. selective insulation, thermal inertia, differential expansion
• CPC Class Codes: F01D 19/00 Starting of machines or engines; Regulating, controlling, or safety means in connection therewith warming-up before starting F01D25/10; turning or inching gear F01D25/34
• CPC Class Codes: F01D 5/26 Antivibration means not restricted to blade form or construction or to blade-to-blade connections or to the use of particular materials
• CPC Class Codes: F01D 5/288 Protective coatings for blades
• CPC Class Codes: F02C 7/26 Starting; Ignition
• CPC Class Codes: F04D 29/321 for axial flow compressors
• CPC Class Codes: F04D 29/584 cooling or heating the machine F04D29/5846, F04D29/5853 take precedence
• CPC Class Codes: F05D 2230/90 Coating; Surface treatment manufacture with deposition of material F05D2230/30
• CPC Class Codes: F05D 2260/85 Starting
• CPC Class Codes: F05D 2300/141 Silver
• CPC Class Codes: F05D 2300/142 Gold
• CPC Class Codes: F05D 2300/224 Carbon, e.g. graphite
• CPC Class Codes: F05D 2300/504 Reflective properties
• CPC Class Codes: F05D 2300/611 Coating

Abstract

A rotor (38) for a gas turbine engine (10) has a low emissivity surface finish, or high emissivity surface finish (44), on at least a portion of its surface (42) to reduce temperature differentials between an upper portion and a lower portion of the rotor (38). This reduces bowing of the rotor (38) to allow the gas turbine engine (10) to be started without harmful vibrations of the rotor (38).

Claims

1-37. -37. (canceled)

38. A gas turbine engine comprising at least one rotor and at least one casing arranged coaxially around the at least one rotor, the rotor having an upper portion, a lower portion and a surface, the at least one casing having a surface, at least one of the at least one rotor or the at least one casing having a surface finish on at least a portion of its surface to reduce the temperature differentials between the upper portion and the lower portion of the at least one rotor, the surface finish being selected from the group comprising a low emissivity surface finish and a high emissivity surface finish, said low emissivity surface finish being selected from the group comprising a polished portion of the surface of the at least one rotor, a machined portion of the surface of the at least one rotor and the at least one casing or a coating applied to the surface of the at least one rotor or the at least one casing.

39. A gas turbine engine as claimed in claim 38 wherein the coating is selected from the group comprising a polished metal coating, a polished silver coating, a polished gold coating and a low emissivity oxide.

40. A rotor for a gas turbine engine having an upper portion, a lower portion and a surface, the surface having a surface finish on at least a portion of thereof to reduce temperature differentials between the upper portion and the lower portion of the rotor, the surface finish being selected from the group comprising a low emissivity surface finish and a high emissivity surface finish, wherein the surface is a radially outer surface of the rotor, a low emissivity surface finish is arranged on at least a portion of the radially outer surface of the rotor wherein the rotor has a radially inner surface and a radially outer surface, a high emissivity surface being arranged on at least a portion of the radially inner surface of the rotor, a high emissivity surface finish being arranged on at least a portion of the radially outer surface of the rotor, a low emissivity surface finish being arranged on at least a portion of the radially outer surface of the rotor and a low emissivity surface finish being arranged on at least a portion of the radially inner surface of the rotor.

41. A rotor for a gas turbine engine having an upper portion, a lower portion and a surface, the surface having a surface finish on at least a portion of thereof to reduce temperature differentials between the upper portion and the lower portion of the rotor, the surface finish being selected from the group comprising a low emissivity surface finish and a high emissivity surface finish, wherein the low emissivity surface finish is selected from the group comprising a polished portion of the surface of the rotor, a machined portion of the surface of the rotor and a coating applied to the surface of the rotor.

42. A rotor for a gas turbine engine as claimed in claim 41 wherein the coating is selected from the group comprising a polished metal coating, a polished silver coating, a polished gold coating and a low emissivity metal oxide.