Local resistivity probe for study of point properties of gas‐liquid flows

Abstract

In this work a resistivity probe for local property measurements, developed originally(1, 2, 3) for (non‐wetting) mercury‐nitrogen flows, was adapted to a broader class of gas‐liquid flows, such as air‐water. To compensate for the non‐negligible dry‐out time of the probe in aqueous systems, a trigger circuit was installed to sense bubble arrival rapidly. Another problem which was solved was the greater tendency for bubbles in water, as compared to mercury, to deflect away from the probe. The probe signal is an instantaneous record of the arrival and departure of bubbles at any point in the flow, and hence is well‐adapted to auto and cross‐correlation measurements, as well as distribution function studies.

Two-phase flow structure of sheet cavitation

“…Different types of local probe have been developed for determining the phase density function in gas-liquid flows. Among these are impedance measurements ͑Nassos and Bankoff; 12 Serizawa et al 13 ͒, the capacitive method ͑Gunn and Al-Doori 14 ͒, hot wire technique ͑Bremhorst and Gilmore 15 ͒, temperature measurements ͑Delhaye et al 16 ͒ and optical techniques ͑Abuaf et al, 17 Cartellier and Achard 18 ͒. In the recent past, new nonintrusive techniques have appeared: X-ray scattering techniques ͑Han and Wesser 19 ͒, nuclear magnetic resonance ͑Javelot et al 20 ͒, and the grating velocimeter-granulometer ͑Cartellier 21 ͒.…”

A Novel Method for Determining the Void Fraction in Gas-Liquid Multi-Phase Systems Using a Dynamic Conductivity Probe

“…The impedance method is a real-time technique with simple equipment requirements [17]. In 1967, Nassos et al [18] utilized a conductance probe to measure the local void fraction of gas-liquid two-phase flow. In 2003, Lv et al [19] conducted experimental research on void fraction measurement in gas-liquid two-phase flow using conductivity probes.…”

Measurement of Water Holdup in Vertical Upward Oil–Water Two-Phase Flow Pipes Using a Helical Capacitance Sensor

“…When the oil is the continuous phase, the flow pattern can be divided into water in oil churn flow (W/O CF), dispersion water in oil flow (D W/O) and very fine dispersion water in oil flow (VFD W/O). Common two-phase flow measurement methods include the conductivity method [9,10], capacitance method [11,12], optical method [13,14], ultrasonic measurement method [15,16], etc. The electrical sensors have the advantages of high sensitivity, a stable signal and convenient use.…”