Study On Flow Measurement Of Small Pipe Diameter By Ultrasonic Frequency Difference Method

In the process of oil recovery,the flow measurement of small pipe diameters is also an important part of improving the recovery rate.Therefore,the flow measurement of small pipe diameters downhole will be the key research direction.The measurement system needs to consider the complex working conditions downhole and the composition of the fluid being measured.Aiming at the problem of small pipe runoff measurement,taking the ultrasonic frequency difference method downhole flow measurement system as the research object,the ultrasonic flow detection method,ultrasonic characteristics and classification as well as transmission characteristics,ultrasonic transducer,fluid characteristic analysis,downhole hardware circuit,software are developed Development and other work.According to the complex working conditions and fluid distribution characteristics of the downhole,relevant analysis and research are carried out theoretically,and ANSYS software is used to analyze the flow velocity distribution of the mixed fluid under different pipe diameters and the solid-liquid two-phase volume in the mixed fluid with different solid content ratios.The distribution law was simulated and simulated,which provided a technical basis for accurate flow measurement.At the same time,the basic parameters and installation method of the transducer are determined according to the measurement method and the pipe diameter.According to the complex working conditions in the well,the electronic devices that fit it are selected,and the related hardware circuits are developed.At the same time,for the processing method of ultrasonic echo signals,this article uses the Zoom FFT algorithm and applies it based on the comprehensive consideration of calculation amount and measurement accuracy.Actual signal processing.A set of small pipe diameter flow measurement system based on ultrasonic frequency difference method is designed.The hardware system includes signal generation and amplification circuit,signal demodulation circuit,etc.,and the software system includes signal transmission module,AD acquisition module,signal processing module and host computer module.Wait.After combining the above components,a relatively complete measurement system was formed,and related simulation tests were carried out to verify the effectiveness of the system.Finally,the small pipe diameter flow measurement system was tested on the mixed fluid with different gears and different solid content of the screw pump.The test results show that the system works normally and can provide theoretical guidance for the flow measurement of small pipes downhole.Combined with actual production,it can be applied to flow measurement downhole.