High Velocity Jet Noise Source Location and Reduction. Task 1. Supplement. Certification of the General Electric Jet Noise Anechoic Test Facility.

摘要

This report summarizes the certification testing of the General Electric Jet Noise Anechoic Test Facility to be used under the subject program. The precision and accuracy of acoustic measurements are evaluated in terms of: anechoic and far-field environment; ambient levels in the chamber; contamination from piping and combustors; contamination from electronic noise floor; variation of the frequency response of the data acquisition and reduction systems; inaccuracies in aerodynamic instrumentation or fluctuations in the jet aero conditions; and precision errors in the air attenuation model due to environmental fluctuations, gradients and measurement inaccuracies. Jet noise measurements from circular conical nozzles are compared with classical reference data.