Gas-Liquid Two-phase Flow Measurement In Gas Well Production

The gas well fracturing and blowout test is an indispensable technical measure for the development evaluation and stimulation of low-permeability reservoirs.The fluid composition during the blow-off test is more complex,mainly based on natural gas and water,and gas under different test stages.The water ratio is quite different.There is no scientific method to accurately calculate the reverse discharge rate.The reverse discharge rate is often calculated by the amount of liquid in the discharge tank.The method is relatively backward and does not consider the influence of the gas in the discharge nozzle on the reverse discharge rate data.This project is based on the measurement and research of gas well discharge.Through the flow measurement and monitoring of gas-liquid two-phase flow during the discharge test,the production status of the gas well can be observed,the gas well productivity can be evaluated and the dynamic changes of the reservoir can be analyzed,and the mining and production can be adjusted.Process,to achieve optimal production is of great significance.In this paper,the propagation characteristics of ultrasonic signals in gas-liquid two-phase flow are studied by COMSOL multiphysics simulation software.The ultrasonic signal is in different diameters and different phases by the distribution of sound pressure and displacement field of the ultrasonic transmitter.The flow velocity of the fluid,the characteristics of the propagation in different fluid media and the simulation of the piezoelectric ceramics indicate the feasibility of using the ultrasonic flow measurement system and determine the operating frequency of the ultrasonic transducer.The piezoelectric ceramics are developed as the core device.Ultrasonic transducer and a set of ultrasonic flow measurement system based on time difference measurement method,including ultrasonic transmitting and receiving module,high precision time difference measuring module,direction switching module,etc.;complete gas-liquid two-phase flow The design of the phase content measurement system includes signal generation and amplification module,sampling module,data storage module,etc.;and the measurement result is displayed on the liquid crystal screen through two-machine communication.The system software and hardware sub-module is debugged to complete the joint debugging and laboratory test of the system.By setting up the simulation test platform,adjusting the screw pump frequency and the liquid volume in the circulation system,the tests are carried out under different fluid flow rates,and the test data is obtained.Organize and analyze.The test results show that the designed flow measurement and phase content measurement system work stably,compact structure and high measurement accuracy,which can basically meet the measurement process conditions under the discharge test environment,and greatly improve the discharge test.The measurement accuracy of the return liquid meets the technical requirements of the design.