[Zurück]

M. Gröschl, M. Kupnik, A. Schröder:
"Adaptive asymmetric double-path ultrasonic transit-time gas flowmeter";
Vortrag: 3rd Congress of the Alps Adria Acoustics Association, Hotel Weitzer, Graz; 27.09.2007; in: "3rd Congress of the Alps Adria Acoustics Association, Hrsg: Joanneum Research", (2007), 4 S.

In this study we demonstrate that a double-path ultrasonic transit-time gas flowmeter (UFM) can be
extended significantly in its rangeability by shifting the two receiving transducers by the same amount in flow direction,
such that the length of one sound path is increased, the other decreased. Such an asymmetric configuration is optimized
in terms of signal-to-noise ratio (SNR) for the range of higher flow velocities, because it compensates for the parasitic
carry-along (sound drift) effect. Further, this approach enables the realization of an adaptive asymmetric UFM, where
the two receiving transducers can be shifted during operation for optimum SNR depending on the gas flow velocity. Our
results show that the asymmetric configuration increases UFM rangeability without drawbacks.

Ultrasonic transit-time flowmeter, asymmetric double-path configuration, sound drift compensation