Gas turbine combustor transition duct forced convection cooling

• US 4,903,477 A
• Filed: 01/10/1989
• Issued: 02/27/1990
• Est. Priority Date: 04/01/1987
• Status: Expired due to Term

• Current Assignee: Siemens Power Generation, Inc.
• Original Assignee: Westinghouse Electric Corporation (Paramount Global (f/k/a ViacomCBS Inc.))
• Inventors: Butt, Graham P.
• Primary Examiner(s): Stout, Donald E.
• Application Number:
  US07/296,353
• Time in Patent Office: 413 Days
• Field of Search: 60/39.37, 60/39.36, 60/760, 60/757, 60/755, 60/758, 60/759, 60/754, 60/751, 60/39.83
• US Class Current: 60/39.37
• CPC Class Codes: F01D 25/14 Casings modified therefor double casings F01D25/26
• CPC Class Codes: F01D 9/023 Transition ducts between combustor cans and first stage of the turbine in gas-turbine engines; their cooling or sealings
• CPC Class Codes: F23R 3/002 Wall structures F23R3/02 and F23R3/007 take precedence

Abstract

In a gas turbine the transition duct is subject to high temperature since it conducts the combustion products to the power turbine. It is normally cooled by air from the compressor. This invention improves the uniformity of cooling by forcing the cooling air to pass over all surfaces of the transition duct. Air flow passages are formed between the ducts and saddle shaped members which direct the flow of air from the compressor over the outer surfaces of the ducts.

Claims

1. In a gas turbine including a compressor for producing an air flow, a plurality of radially arranged combustors for producing hot combustion gases supplied with air from said compressor, a power turbine, transition ducts coupling said hot combustion gases from said combustors to said power turbine;

means to equalize the surface temperature of said transition ducts comprising saddle shaped members overlying a substantial portion of the radially outward surfaces of said transition ducts to direct the said air flow from said compressor to said combustors substantially uniformly over said outward surfaces of said transition ducts, a seal wall through which said transition ducts pass, said seal wall separating the compressor output from said combustors and forcing all of said airflow from the compressor to flow through apertures in said wall in its path to said combustors.

2. In a gas turbine as claimed in claim 1 a saddle shaped member spaced from the upper surface of said transition duct and mounted at its one end on said seal wall and at its other end on the frame of said power turbine.

3. A gas turbine including a compressor to provide air flow to a plurality of combustors arranged radially around said compressor which provide combustion gases to a power turbine axially aligned with the coupled to said compressor, a plurality of transition ducts coupling said combustion gases from said combustors to said power turbine, means to equalize the temperature of the surfaces of said transition ducts comprising;

saddle shaped members spaced radially outwards from said transition ducts and overlying a substantial portion of said transition ducts and forming between said ducts and said saddle shaped members, air ducts and means to cause a substantial portion of the airflow from said compressor to said combustors to flow through said air ducts, including a wall separating the output end of the compressor from said combustors, apertures in said wall through which said transition ducts pass, said saddle shaped members being supported at one end by said wall and said apertures being sufficiently large as to permit nonturbulent flow of air from said compressor around said transition ducts and through the gaps between the transition ducts and the wall to the combustors.