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A Double Transducer for High Precision Ultrasonic Time-Domain Reflectometry Measurements.

Stade S, Hakkarainen T, Kallioinen M, Mänttäri M, Tuuva T - Sensors (Basel) (2015)

Bottom Line: A double transducer described in this study eliminates the need for a separate reference transducer because in the double transducer the reference measurement is included in the design of the transducer holder.Two sensors in the same holder require less space.Other advantage is that the double transducer can be placed near the measurement target and hence the local sonic velocity can be determined.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Separation Technology, School of Engineering Science, Lappeenranta University of Technology, P.O. Box 20, Lappeenranta FI-53851, Finland. stade@lut.fi.

ABSTRACT
Membrane fouling, where unwanted particles accumulate on the membrane surface and reduce its permeability, causes problems in membrane filtration processes. With ultrasonic time-domain reflectometry (UTDR) it is possible to measure the extent of membrane fouling and hence take actions to minimize it. However, the usability of UTDR is very limited to constant filtration conditions if the sonic velocity, which has a great impact on UTDR measurement accuracy, is unknown. With a reference transducer the actual sonic velocity can be measured. This requires another transducer to be installed in the module, where there may be only limited space or the module dimensions may not be suitable for the reference transducer. A double transducer described in this study eliminates the need for a separate reference transducer because in the double transducer the reference measurement is included in the design of the transducer holder. Two sensors in the same holder require less space. Other advantage is that the double transducer can be placed near the measurement target and hence the local sonic velocity can be determined.

No MeSH data available.


Calibration measurement of double transducer. Time was measured at 10 different distances. Sonic velocity was same with both transducers (1491 m/s) and distance between transducers is 561 µm (= 4256 − 3695).
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sensors-15-15090-f006: Calibration measurement of double transducer. Time was measured at 10 different distances. Sonic velocity was same with both transducers (1491 m/s) and distance between transducers is 561 µm (= 4256 − 3695).

Mentions: The calibration results are shown in Figure 6. As can be seen from the figure, the measured time versus distance change forms two linear lines. The sonic velocity is determined from the slopes of these lines and it correlates with the value calculated with an equation developed by Belogol’skii, Sekoyan et al. [16] (1491 m/s, 1 bar, 23 °C). The equation can be used to calculate the sonic velocity in water as a function of temperature and pressure. The equation and its use have been previously explained in depth by Stade et al. [14].


A Double Transducer for High Precision Ultrasonic Time-Domain Reflectometry Measurements.

Stade S, Hakkarainen T, Kallioinen M, Mänttäri M, Tuuva T - Sensors (Basel) (2015)

Calibration measurement of double transducer. Time was measured at 10 different distances. Sonic velocity was same with both transducers (1491 m/s) and distance between transducers is 561 µm (= 4256 − 3695).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4541822&req=5

sensors-15-15090-f006: Calibration measurement of double transducer. Time was measured at 10 different distances. Sonic velocity was same with both transducers (1491 m/s) and distance between transducers is 561 µm (= 4256 − 3695).
Mentions: The calibration results are shown in Figure 6. As can be seen from the figure, the measured time versus distance change forms two linear lines. The sonic velocity is determined from the slopes of these lines and it correlates with the value calculated with an equation developed by Belogol’skii, Sekoyan et al. [16] (1491 m/s, 1 bar, 23 °C). The equation can be used to calculate the sonic velocity in water as a function of temperature and pressure. The equation and its use have been previously explained in depth by Stade et al. [14].

Bottom Line: A double transducer described in this study eliminates the need for a separate reference transducer because in the double transducer the reference measurement is included in the design of the transducer holder.Two sensors in the same holder require less space.Other advantage is that the double transducer can be placed near the measurement target and hence the local sonic velocity can be determined.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Separation Technology, School of Engineering Science, Lappeenranta University of Technology, P.O. Box 20, Lappeenranta FI-53851, Finland. stade@lut.fi.

ABSTRACT
Membrane fouling, where unwanted particles accumulate on the membrane surface and reduce its permeability, causes problems in membrane filtration processes. With ultrasonic time-domain reflectometry (UTDR) it is possible to measure the extent of membrane fouling and hence take actions to minimize it. However, the usability of UTDR is very limited to constant filtration conditions if the sonic velocity, which has a great impact on UTDR measurement accuracy, is unknown. With a reference transducer the actual sonic velocity can be measured. This requires another transducer to be installed in the module, where there may be only limited space or the module dimensions may not be suitable for the reference transducer. A double transducer described in this study eliminates the need for a separate reference transducer because in the double transducer the reference measurement is included in the design of the transducer holder. Two sensors in the same holder require less space. Other advantage is that the double transducer can be placed near the measurement target and hence the local sonic velocity can be determined.

No MeSH data available.