Measuring high frequency valve noise to evaluate interference with ultrasonic flow meters

Ultrasonic flow meters are installed in lines with particular concern on the location of flow noise sources, such as valves and other geometry changes and restrictions in a piping system. The ultrasonic flow meter operates with a tone burst, typically in the range of 100 to 300 kHz. While this frequency range is far above the typical range for noise control in piping systems, there is good evidence that the flow noise sources generate sound in the operating frequency range of the ultrasonic flow meter. The goal of the work was to establish a procedure to measure the noise generated by piping elements in the frequency range of the ultrasonic flow meter operation. The flow disturbance is placed upstream of the ultrasonic flow meter. The internal noise spectrum are measured at three locations: one upstream of the flow disturbance, one between the flow disturbance and the flow meter, and one downstream of the flow meter. Some available results in the literature will be reviewed along with presenting the experimental setup and preliminary results. The results will show the capabilities of the measurements in this frequency range.