Accession Number:

ADA158092

Title:

Time-Resolved Flowfield Measurements in a Turbine Stage.

Descriptive Note:

Master's thesis,

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s):

Report Date:

1985-06-01

Pagination or Media Count:

166.0

Abstract:

Time-resolved flowfield measurements for a 0.5-meter diameter, high work transonic turbine have been completed in the MIT Turbine Blowdown Facility TBF. Measurements were taken to determine the blade-to-blade total temperature profile for comparison with predictions from the Euler turbine equation to determine the effect of using time-averaged pressures to calculate turbine performance and to provide a complete set of time-resolved turbine stage data. A preliminary objective given a 6 kHz blade passing frequency was to determine the frequency response characteristics of the instrumentation used to make the flowfield measurements. A shock tube was built for this purpose. Measurements were taken with high-frequency response instrumentation including a dual-hot-wire aspirating probe, a four-way angle probe, and two cobra head total pressure probes incorporating silicon diaphragm pressure transducers. The aspirating probe is found to have a natural frequency of 15.5 kHz in the test gas with a damping ratio of 0.36 the angle probe a characteristic frequency of 45 kHz with a settling time of 18 usec. Both results are satisfactory for application in the TBF. The measured total temperature profile shows a peak-to-peak variation of 65 C 20 and a characteristic frequency twice that of the blade passing frequency. Theses

Subject Categories:

  • Test Facilities, Equipment and Methods
  • Fluid Mechanics
  • Jet and Gas Turbine Engines

Distribution Statement:

APPROVED FOR PUBLIC RELEASE