2017 Volume 16 Pages 73-79
This paper describes a testing method to measure acoustic and thrust characteristics of exhaust nozzles using a model engine and the uncertainty analysis of this method. The uncertainty in the measurement of gross thrust coefficient and 1/3 octave band sound pressure levels in the model engine test were estimated to be ±0.6 % and ±0.41 dB, respectively. Although there are a few differences between the reference data of jet noise and the obtained data, it was demonstrated that the proposed method provides both acoustic and thrust data with reasonably good repeatability and also allows us to conduct a simulated flight test of hot-jets. A demonstration using a noise reduction nozzle was also performed to demonstrate the usefulness of the proposed method, and it clearly emphasized the difference between a baseline nozzle and a noise reduction nozzle with the estimated uncertainty.
