Tip Sensor Development

Abstract

Turbomachinery blade clearance and time of arrival sensors based on the Vatell eddy current principle, and suitable for operation at temperatures up to 200 degrees C, were designed, built and tested on the first fan stage of a JT15-D. The sensors produced robust, low noise signals whose general shape is virtually independent of speed, and whose amplitudes are related to speed and clearance. The signals of individual blades were readily resolved and identified. A model equation which predicts sensor signal amplitude, given values of clearance and speed, was developed, and coefficients derived to fit the experimental data. The engine was equipped with an optical once/revolution sensor.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1988
Accession Number
ADA200080

Entities

People

  • Lawrence W. Langley

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Air Force
  • Amplitude
  • Clearances
  • Coefficients
  • Detectors
  • Eddy Currents
  • Equations
  • High Temperature
  • Identification Systems
  • Lead Wires
  • Light Sources
  • Magnet Coils
  • Magnetic Fields
  • Materials
  • Measurement
  • Optical Detectors

Readers

  • Aerodynamics.
  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Sensor Fusion and Tracking Systems.