Optical multi-point measurements of the acoustic particle velocity with frequency modulated Doppler global velocimetry.
To reduce the noise of machines such as aircraft engines, the development and propagation of sound has to be investigated. Since the applicability of microphones is limited due to their intrusiveness, contactless measurement techniques are required. For this reason, the present study describes an optical method based on the Doppler effect and its application for acoustic particle velocity (APV) measurements. While former APV measurements with Doppler techniques are point measurements, the applied system is capable of simultaneous measurements at multiple points. In its current state, the system provides linear array measurements of one component of the APV demonstrated by multi-tone experiments with tones up to 17 kHz for the first time.
Laboratory for Measurement and Testing Techniques, Technische Universität Dresden, Helmholtzstrasse 18, 01062 Dresden, Germany. andreas.fischer2@tu-dresden.de
Andreas
A
Fischer
Jörg
J
König
Daniel
D
Haufe
Raimund
R
Schlüssler
Lars
L
Büttner
Jürgen
J
Czarske
D000162:Acoustics / Q000295:instrumentation; D000401:Aircraft; D004301:Doppler Effect; D004867:Equipment Design; D005583:Fourier Analysis; D017078:Laser-Doppler Flowmetry / Q000295:instrumentation / Q000379:methods*; D016014:Linear Models; D009038:Motion; D009624:Noise, Transportation / Q000517:prevention & control*; D011312:Pressure; D013997:Time Factors; D035501:Uncertainty