Accession Number : ADP005549

Title :   Compressor Blade Clearance Measurement Using Capacitance and Phase Lock Techniques,

Corporate Author : AIR FORCE WRIGHT AERONAUTICAL LABS WRIGHT-PATTERSON AFB OH

Personal Author(s) : Demers,Rosario N.

Report Date : NOV 1986

Pagination or Media Count : 10

Abstract : The clearance measurement system described in this paper has several unique features which minimize problems plaguing earlier systems. These include tuning stability and sensitivity drift. Both these problems are intensified by the environmental factors present on compressors i.e., wide temperature fluctuations, vibrations, conductive contamination of probe tips and others. The circuitry in this new system provides phase lock feedback to control tuning and shunt calibration to measure sensitivity. Use of high frequency excitation lowers the probe tip impedance thus minimizing the effects of contamination. A prototype has been built and tested. The ability to control tuning and to calibrate has been demonstrated. An eight channel system is now being constructed for use in the Compressor Research Facility at Wright-Patterson AFB OH.

Descriptors :   *COMPRESSOR BLADES, CLEARANCES, TOLERANCES(MECHANICS), ELECTRICAL MEASUREMENT, CAPACITANCE, PHASE LOCKED SYSTEMS, FEEDBACK, CIRCUITS, EXCITATION, HIGH FREQUENCY, MULTICHANNEL, PHASE DETECTORS, JET ENGINES

Subject Categories : Test Facilities, Equipment and Methods
      Jet and Gas Turbine Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE