A water holdup measurement method for near-horizontal oil-water two-phase flow

Abstract

The invention relates to a method for measuring a water holding rate of a near-horizontal oil-water two-phase flow. A measuring device used by the method comprises a test pipe, an upstream fast-closing valve, a downstream fast-closing valve and an array of double-parallel line conductivity sensors. The two fast-closing valves are respectively arranged at two ends of the test pipe. The double-parallel line conductivity sensors are distributedly inserted into different cross sections of the test pipe. The test pipe is fixed in an experimental pipe. When a flow can stably flow, the upstream and downstream fast-closing valves are fast closed, after the oil-water two-phase flow in the pipe to be detected is layered through standing, the double-parallel line conductivity sensors in the oil-waterinterface carry out acquisition and processing of signals so that height hw of water layers at the double-parallel line conductivity sensor positions and sensor position parameters n are obtained, and a water holding rate is calculated through the hw and n.

Description

technical field [0001] The invention relates to a method for measuring the water holdup of a near-horizontal oil-water two-phase flow in the test of a liquid production profile of a horizontal well in the field of oil field dynamic monitoring. Background technique [0002] As a very efficient means of oil and gas extraction, horizontal wells can greatly increase the single well productivity and ultimate recovery of oil and gas fields. Horizontal well oil extraction technology is called the second technological revolution. During the drilling process of horizontal wells, there will be certain errors in the control of the drilling trajectory, so that there is a small angle (generally less than 5°) between the axis of the wellbore and the horizontal direction, forming a near-horizontal wellbore. When the flow rate in the well is low, due to the intensified gravity separation between oil and water, the fluid flow in the wellbore presents a significant laminar flow distribution s...

AI Technical Summary

Problems solved by technology

However, in the horizontal and near-horizontal oil-water two-phase flow environment, when the fluid between the quick-closing valves is drained to the outside of the pipe, there will be more residual fluid on the pipe wall, which will cause errors in the measurement of water holdup. At the same time, directly measure the water layer or oil layer outside the pipe section When the height is high, the reading error of the water layer height caused by the light refraction will also cause the water holdup measurement error

In addition, due to the small difference in density between the oil-water two-phase flow, the accuracy of measuring the water holdup of oil-water two-phase flow by other methods such as ray method or differential pressure method is low

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