Development of an Aeroacoustic Methodology to Evaluate Heatshield Material Performance
Abstract
An experimental program was conducted in the AFWAL Mach 6 and AEDC shock Tube facilities in which acoustic fluctuating pressure data were acquired on flat plate TWCP specimens featuring smooth and rough surfaces. The TWCP specimens were instrumented with five Gulton microphones. The microphones placed in the model consisted of flush, ported, and backface (blind hole) locations. Several l/d ported orifices were examined as well as depths from the boundary layer surface for the backface gages. The AEDC tests were structured to examine optimum ported orifices prior to the AFWAL Mach 6 tests. The TWCP specimens were exposed to turbulent boundary layer conditions at tunnel stagnation pressures of 700, 1400, and 2100 psi with a total temperature of 1100 deg. R, respectively. A correlation was developed for the ported hole sensors that can be related to the flush mounted sensors. Characterizing the backface (blind hole) gages with surface mounted sensors will require further data interpretation due to vibration. In general, rough walls augmented the acoustic energy levels as expected. A biased rough pattern (20 deg, angled to flow) indicated that acoustic measurements could be used as a diagnostic technique to determine the surface characteristics of TWCP ablation patterns.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1982
- Accession Number
- ADA115606
Entities
People
- A. L. Laganelli