A NOVEL AUXILIARY BEARING FOR TURBINE ENGINES

THE AUXILIARY BEARINGS WILL BE CRITICAL COMPONENT OF ADVANCED GAS TURBINE ENGINES THAT USE MAGNETIC BEARINGS TO SUPPORT AND POSITION THE ENGINE SPOOLS. BECAUSE OF THE HIGH TEMPERATURES IN THE BEARING COMPARTMENTS, CONVENTIONAL OIL LUBRICATED BEARINGS CANNOT BE USED EITHER AS THE MAIN OR AUXILIARY BEARINGS. ALTHOUGH SOLID LUBRICATED BEARINGS UNDER DEVELOPMENT ARE CAPABLE OF SUPPORTING HIGH LOADS AT HIGH TEMPERATURES, THEIR SHORT LIFETIME LIMITS THEIR USE FOR MANRATED AIRCRAFT ENGINES. THE PROPOSED INNOVATION WILL POTENTIALLY OVERCOME THIS LIMITATION. A NOVEL BEARING CONFIGURATION COMBINES THE ATTRIBUTES OF SOLID AND GAS-FILM LUBRICATION. UNDER CONDITIONS OF LIGHT LOADING, THE ENGINE SHAFT IS SUPPORTED BY A GAS-FILM WITHOUT MECHANICAL FRICTION OR WEAR. HIGH LOADS OF SHORT DURATION ARE SUSTAINED BY DRY LUBRICATED SURFACES, WHICH MAY BE EITHER COATED OR POWDER-FED. THE AUXILIARY BEARING ALSO INCLUDES AN INTERFACE WITH THE MAGNETIC BEARING CONTROLLER FOR SIGNALING WHEN BEARING OVERLOADS WILL OCCUR. IN PHASE I, THE FEASIBILITY OF THE AUXILIARY BEARING CONCEPT WILL BE ASSESSED, AND A PRELIMINARY DESIGN WILL BE DEVELOPED. THE AUXILIARY BEARINGS WILL BE BUILT AND TESTED IN PHASE II. CREARE WILL WORK WITH ENGINE MANUFACTURERS IN PHASE III TO INCORPORATE THE AUXILIARY BEARINGS INTO ADVANCED ENGINES.