Turbine cooling air deswirler

• US 4,541,774 A
• Filed: 08/01/1983
• Issued: 09/17/1985
• Est. Priority Date: 05/01/1980
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Kirkpatrick, Ralph A., Rieck, Harold P.
• Primary Examiner(s): Yuen, Henry C.
• Assistant Examiner(s): Kwon, John
• Application Number:
  US06/518,762
• Time in Patent Office: 778 Days
• Field of Search: 415/115, 415/116, 415/175, 415/176
• US Class Current: 415/115
• CPC Class Codes: F01D 5/085 cooling fluid circulating inside the rotor
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A device is provided for efficiently directing nonrotating cooling air into a rotating turbine rotor. The device employs a nozzle to accelerate the cooling air in the direction of rotor rotation. A diffuser-deswirler then directs this air, with curved and expanding flow passages, into corresponding holes in the turbine rotor. With these elements, the device directs the cooling air into the rotating rotor section without significant pressure losses and with a lower resultant cooling air temperature.

Claims

1. In a gas turbine engine having a compressor, a combustor, a rotating turbine section around a central engine axis with associated turbine rotors and a rotating turbine shaft, and a cooling air circuit for providing cooling air into said rotating turbine section through holes in said shaft, said cooling air circuit including means for directing said cooling air into said rotating turbine section with a minimum pressure loss and maximum decrease in temperature, comprising in combination:

(a) a nozzle for receiving said cooling air in a direction radially inward and substantially perpendicular to said central engine axis, said nozzle being of the convergent type such that in passing through said nozzle the velocity of said air is increased, the temperature and pressure of said air are decreased and said cooling air exits said nozzle at a direction substantially tangential to and in the same direction of rotation as said rotating turbine shaft; and

(b) a deswirler directly attached to said turbine shaft for rotation therewith, wherein said deswirler includes a plurality of internal turning vanes which extend backwardly in the direction of said rotation and form passages which curve progressively from said substantially tangential direction toward the perpendicular to said central engine axis, and wherein said turning vanes and passages are rotated away from the cooling air exiting said nozzle, and wherein said passages further comprise;

(i) entrance regions between said vanes which are aligned in serial flow relationship with the cooling airflow exiting said nozzle for aerodynamically accepting said exiting cooling air and wherein said entrance regions initiate a transformation of the substantially tangential velocity of the airflow exiting said nozzle into radial and tangential components by curving the cooling airflow in a radially inwardly direction;

(ii) intermediate regions having a progressively increasing cross-sectional area for decelerating and diffusing said cooling air and for continuing to curve the direction of said cooling airflow in a radially inward direction thereby continuing the transformation of cooling air tangential velocity into radial and tangential components such that said tangential component generally matches the rotational velocity of said turbine shaft; and

(iii) exit regions between said vanes, which are generally aligned in serial flow relationship with said holes in said turbine shaft for aerodynamically directing said cooling air into said turbine shaft,

wherein said deswirler passages convert approach velocity head of the cooling air entering said entrance regions into static pressure which static pressure is greater than the pressure of the cooling air entering said deswirler and minimally less than the pressure of the cooling air entering said nozzle and wherein the temperature of said cooling air exiting said deswirler is lower than that of the cooling air entering said nozzle.