A methodology to quantify the systematic uncertainty in the liquid holdup measurements with Wire Mesh Sensor


A methodology to quantify the systematic uncertainty in the liquid holdup measurements with Wire Mesh Sensor

Vuong, D.; Aydin, T. B.; Torres, C. F.; Schleicher, E.; Pereyra, E.; Sarica, C.

The systematic uncertainty in the holdup measurements of a capacitance based WMS has been experimentally evaluated, and a methodology for its quantification is proposed. Tests are conducted in laboratory and in-situ conditions for different mesh grid and pipe inclination angles, and different flow conditions in a high pressure (1.37 MPa) facility with a range of gas and liquid velocity ranges of 2.8 m/s ≤ νSg ≤ 6.9 m/s and 1 cm/s ≤ vSL ≤ 5 cm/s, respectively.
The angle between the phase interface and the sensor wires is ineffective while the pipe inclination angle plays a major role in the deviations of the holdup measurements. Using the proposed methodology, the systematic uncertainty is shown to follow a logarithmic increase as a function of the measured holdup for smaller holdup values (HL ≤ 15%) and to be lower than 1.5% for HL > 15%. This behavior is representative of the systematic uncertainty in the actual flow loop installation.
Under actual flow conditions, the holdup measurements of the trapped liquid by WMS show an Offset compared to the Canty measurements which can be corrected by using the quantified uncertainty in the laboratory tests. Furthermore, the dynamic measurements with WMS show a good agreement with the holdup of the trapped liquid volume within the quantified uncertainty bounds.

Keywords: wire mesh; systematic uncertainty; calibration; two-phase flow

Permalink: https://www.hzdr.de/publications/Publ-21786
Publ.-Id: 21786