An investigation of sonic and ultrasonic
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E. Olsen
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Article
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1991
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Elsevier Science
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English
โ 199 KB
Several different specially designed flowmeters, both in the sonic frequency region, f = 3.1 kHz, and the ultrasonic frequency region, f = 40 kHz, for measuring air velocities were investigated. Special emphasis was given to measurements of very low air velocities, i.e. lower than 1 m s-1. The flowm