XVIII IMEKO WORLD CONGRESS Metrology for a Sustainable Development September, 17 – 22, 2006, Rio de Janeiro, Brazil IMPROVEMENT OF ULTRASONIC CROSS-CORRELATION MEASUREMENT OF GAS FLOW BY BLUFF BODY GENERATED VORTICES
نویسندگان
چکیده
Ultrasonic cross-correlation flow meters using natural turbulences in a fluid must be calibrated. The reason is that the most frequent components in the fluid are determined by this method deviating from the average flow velocity. The calibration characteristic is nonlinear and depends on the flow velocity and profile, respectively. This disadvantage can be avoided by small artificially generated vortices combined with cross-correlation measurement. In this case the vortices are travelling with average flow velocity. The detection of travelling time of a group of vortices between two ultrasonic barriers by cross correlation admits the direct determination of the average flow velocity. Furthermore, the combination of vortex and correlation measurement results in a self-monitoring system.
منابع مشابه
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