Accession Number:

AD0772805

Title:

Pneumomechanical Critical Speed Control for Gas Turbine Engine Shafts.

Descriptive Note:

Technical rept. 30 May 72-Sep 73,

Corporate Author:

MECHANICAL TECHNOLOGY INC LATHAM N Y

Report Date:

1973-11-01

Pagination or Media Count:

115.0

Abstract:

Initial evaluation of the use of gas-lubricated intershaft foil bearings to reduce inner spool vibration levels in small gas-turbine aircraft engines has been successfully concluded. A Hydresil intershaft foil bearing was applied to a power turbine shaft simulator operating on elastically-mounted ball bearings without support damping. A series of tests showed that the two-pad and three-pad Hydresil bearings are superior to the 360-degree bearing for the journal size and rotor speeds tested. Rotor balancing via the recently-developed MTI Multiplane-Multispeed Balancing Procedure was used to suppress the first bending shaft-bearing system critical speed and a pedestal resonance, and to leave a distinct vibration peak at the second bending critical speed. Modified author abstract

Subject Categories:

  • Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE