Research on Water Holdup Detection Method and Tool Design Using Conical Spiral Transmission Line

Abstract

Aiming at the problem of dynamic monitoring of horizontal well, this paper studies the oil-water two-phase water holdup detection method based on transmission line, the design of micro-sensor and the development of array water holdup detection tool. The model of the relationship between the dielectric constant of the filling medium of the general transmission line and the amplitude and phase shift of the electromagnetic wave signal on the transmission line is established by using the time-domain analysis method. Four common transmission lines are analyzed, and a novel method for measuring the water holdup of oil-water mixtures based on phase shift of signals on conical spiral is proposed. The structural parameters of the conical spiral transmission line are simulated and optimized by software simulation method, and a small conical spiral water holdup sensor suitable for arraying is invented. The sensor has a size of 30 mm × 6mm (height × cone base diameter). Its volume is 0.28 cm3, is only 1/160 of the current coaxial transmission line sensor volume, and only 1/3 of the current smallest capacitance and conductance water holdup sensors, realizing the senor miniaturization. The experimental results show that the sensor can realize the full scale measurement of well water holdup from 0% to 100%, and the measurement error is less than 3%. On this basis, 12 sensors are used to form a clock-like detection array. The first array water holdup detection tool based on transmission line is developed, which realizes the array detection of the cross-section medium distribution information of horizontal wells.