TY - GEN
T1 - UNCERTAINTY FACTORS IN PROPELLER AEROACOUSTIC MEASUREMENTS
AU - Wu, Han
AU - Jiang, Hanbo
AU - Zhou, Peng
AU - Zhong, Siyang
AU - Zhang, Xin
N1 - Funding Information:
This work is supported by the Hong Kong Research Grant Council (RGC 16202520) and the National Natural Science Foundation of China (NSFC 11972029).
Publisher Copyright:
© International Institute of Acoustics and Vibration (IIAV), 2022.
PY - 2022/7
Y1 - 2022/7
N2 - The increasing engagement of multi-rotor powered flying vehicles has attracted interest in recent years. The propeller noise is a major aerodynamic noise source. Aerodynamic and acoustic measurements in an anechoic environment are often made to characterize noise. However, there are several inevitable uncertainty factors in experiments, including unsteady speed fluctuations, manufacturing imperfection and flow disturbances, which can affect the measurement results. Systematic investigations to identify and quantify the influence of these factors are rare. In this work, the effects of these uncertainty factors are quantified based on synchronized measurements. Results show that the rotational speed fluctuations can lead to random variations of tonal noise. The dynamic imbalance due to manufacturing imperfection can be indicated by force fluctuations and result in significant tones at shaft harmonics. Flow disturbances can be caused by flow recirculation in anechoic chambers, amplifying noise generation. The onset time of recirculation can be estimated by the propeller diameter and averaged thrust.
AB - The increasing engagement of multi-rotor powered flying vehicles has attracted interest in recent years. The propeller noise is a major aerodynamic noise source. Aerodynamic and acoustic measurements in an anechoic environment are often made to characterize noise. However, there are several inevitable uncertainty factors in experiments, including unsteady speed fluctuations, manufacturing imperfection and flow disturbances, which can affect the measurement results. Systematic investigations to identify and quantify the influence of these factors are rare. In this work, the effects of these uncertainty factors are quantified based on synchronized measurements. Results show that the rotational speed fluctuations can lead to random variations of tonal noise. The dynamic imbalance due to manufacturing imperfection can be indicated by force fluctuations and result in significant tones at shaft harmonics. Flow disturbances can be caused by flow recirculation in anechoic chambers, amplifying noise generation. The onset time of recirculation can be estimated by the propeller diameter and averaged thrust.
KW - aeroacoustic measurement
KW - propeller noise
KW - uncertainty analysis
UR - http://www.scopus.com/inward/record.url?scp=85149874742&partnerID=8YFLogxK
M3 - Conference article published in proceeding or book
AN - SCOPUS:85149874742
T3 - Proceedings of the International Congress on Sound and Vibration
BT - Proceedings of the 28th International Congress on Sound and Vibration, ICSV 2022
PB - Society of Acoustics
T2 - 28th International Congress on Sound and Vibration, ICSV 2022
Y2 - 24 July 2022 through 28 July 2022
ER -