同轴线式相位法测量油井含水率

本文利用同轴传输线作传感器，测量油水混合水质的相位系数，研制了同轴线式相位法找水仪，从而得到油水混合介质的持水率。该仪器还实现了油井持水率以往难达到的连续测量，室内模拟井试验和初步现场试验看出本文提出的含水率测量新方法颇有前途。     

基于AD5933电阻测量芯片的持水率检测方法

文中基于AD5933电阻测量芯片提出了一种电阻式持水率检测方法。该方法通过AD5933检测被测流体的阻抗和相角,从而计算出流体的电阻值,能够显著降低检测传感器分布电容对油水两相流体电阻率测量结果的影响。实验结果表明,该方法能够准确地测量两相流体的电阻值;当持水率大于50%,且油水两相流为两相分离的泡状流时,该方法可以很好地用于井下油水两相流体持水率的检测。     

基于BP神经网络的原油持水率检测仪

针对传统电磁波传感器输出信号与持水率难以线性化的缺点,综合单片机和BP神经网络的优点,研制出基于MSP430F5529单片机和BP神经网络的原油持水率检测仪。通过MSP430F5529检测电磁波传感器输出相位差信号,经低通滤波和A/D转换后得到与持水率相对应的电压值,将实时温度和电压值送BP神经网络进行训练。该仪器首次将单片机与人工神经网络相结合用于原油持水率检测,具有响应时间短、精确度高、功耗低等优点,能方便实时地检测出原油持水率,具有很强的实用性。     

一种细长矩形截面传输线成型工艺

定向耦合器是用来实现信号检测的无源微波组件,插入损耗是其一项重要性能指标,而矩形截面的传输线是低插入损耗同轴宽带定向耦合器的核心零件之一。为了提高该类传输线的表面状态特性,降低插入损耗,根据矩形截面传输线的结构特点,改变了以往采用精密慢走丝线切割加工的传统成型工艺方法,通过高速铣削的引入、工艺装夹方式的改进以及加工参数优化和后处理方式的改进等,实现了超细长矩形截面传输线高速铣削加工成型,在改善零件表面质量的同时,也较大幅度地提高了信号传输性能,取得了满意的效果。     

一种石油生产永置式地面井口持水率动静态测量装置研究

为满足采油地面井口多相流持水率测量的实际要求,本文结合电导动态测量与筒状电容静态测量技术,研制了一种永置式石油生产地面井口多相流持水率动静态测量装置(PDSWHMD＿SM)。具体地,文中采用有限元方法(FEM)构建了电导-电容一体式传感器(CCIS)数值模型,在此基础上对CCIS管道内流体处于流动及静止状态下分相介质的分布特性、CCIS结构参数、CCIS电学分布特性、不同多相流工况下的响应特性等进行了深入研究,最终确定了CCIS最优结构参数：H_e=90 mm、ID=30 mm、Ih_e=3 mm、H_c=375 mm、IR₁=26 mm、T_c=1 mm、H_m=56 mm,证明了其测量误差在5%以内。另外,本文以总流量5～70 m³/d,持水率50%～90%等多相流工况为例进行了实验研究,实验结果表明：研制的装置PDSWHMD＿SM持水率测量误差同样在5%以内。仿真和实验均证明了PDSWHMD＿SM具有良好的持水率测量性能。     

梯形变截面悬臂梁式质量传感器设计与分析EI北大核心CSCD

谐振式微质量传感器的灵敏度取决于弹性元件的几何尺寸和结构形式。单纯依靠结构尺寸微型化方法已难以满足传感器工程实用性的要求,因而需要探索新的改善传感器性能的方法。在保证传感器外形尺寸不变的基础上,提出通过改变弹性梁的表面形状(梯形)和截面构型(槽型)来进一步提升传感器灵敏度的新方法,建立了基于槽型变截面弹性梁的传感器灵敏度分析模型,分析了影响传感器灵敏度的关键设计因素,得到了结构设计参数、自振频率及灵敏度之间的关系表达式。仿真结果表明,在相同外形尺寸参数下,矩形截面悬臂梁传感器的自振频率和质量检测灵敏度为1 254.2 Hz和9.8×103Hz/g,槽型变截面悬臂梁传感器的自振频率和灵敏度为1 776.1 Hz和38.0×103Hz/g。相对于矩形截面梁传感器,灵敏度提高了287.8%,从而验证了提出的灵敏度提升方法的有效性和可行性。     

接触线参数双目视觉测量系统的有效视场与分辨率分析

根据双目测量系统的特点和接触线参数检测的技术要求,分析了双目视觉法测量接触线的有效视场和分辨率与系统结构参数和摄像机光学参数的理论关系.应用MATLAB软件对不同结构参数和光学参数条件下的有效视场和分辨率进行仿真计算.结果表明图像传感器CCD的光敏面尺寸和像素尺寸分别是影响有效视场和分辨率的主要因素;对于确定的CCD,焦距增大,有效视场减小,分辨率提高;而且,对接触线高度的测量分辨率远低于对拉出值的测量分辨率.     

集流型测试仪在斜井中的响应研究

1 引言 油井倾斜后,由于受井斜、流量、含率、轻质相和重质相密度差等因素的影响,井筒中出现重质相倒流、分层等现象[1,2],从而对流动参数的准确测量产生很大影响.本文主要针对油井多参数组合仪在斜井中测量流量和持水率的响应问题进行实验研究,目的在于解决斜井油水两相流动产出剖面的测试问题.     

单条纹截面轮廓传感器的设计与标定

为实现单条纹截面轮廓传感器的设计与标定,建立了单条纹截面轮廓传感器测量物体表面点空间坐标的数学模型,基于此模型分析了单条纹截面轮廓传感器的测量误差,得出了传感器各结构参数与测量误差之间的关系.在综合分析各结构参数对测量误差的影响的基础上,得出了传感器结构参数设计的依据,并给出了结构参数设计及标定的实例.最后,通过实验的方法对传感器的测量精度进行了验证.实验结果表明:深度测量相对误差＜0.3%,重构的复杂表面具有良好的视觉效果.     

单条纹截面轮廓传感器设计与标定

为实现单条纹截面轮廓传感器的设计与标定,建立了单条纹截面轮廓传感器测量物体表面点空间坐标的数学模型,基于此模型分析了单条纹截面轮廓传感器的测量误差,得出了传感器各结构参数与测量误差之间的关系。在综合分析了各结构参数对测量误差的影响的基础上,得出了传感器结构参数设计的依据,并给出了结构参数设计及标定的实例,最后通过实验的方法对传感器的测量精度进行了验证。实验结果表明：深度测量相对误差小于0.3%,重构的复杂表面具有良好的视觉效果。     

Liquid holdup measurement in horizontal oil–water two-phase flow by using concave capacitance sensor

Due to the complex flow structures of horizontal oil–water flows, the liquid holdup measurement is still a challenging problem. In this paper, we using the finite element analysis build a two-dimensional model of the concave capacitance sensor and investigate the effect of sensor geometry on the distribution of the sensitivity field. Through calculating the sensor static response for different horizontal oil–water flow patterns, we figure out the optimum geometry of the concave capacitance sensor. In addition, we conduct experiment to obtain the measured response of the concave capacitance sensor and achieve the oil-holdup by using quick closing valve. The results indicate that the optimized concave capacitance sensor shows good performance for liquid holdup measurement of horizontal oil–water two-phase flow.     

原油含水率红外光谱测量的超稀疏表示方法

油水混合物的光谱分析方法已经成为当前油水两相流测量的研究热点。然而,传统的油水混合物光谱分析中,一般是通过主成分分析、连续投影算法等降维技术实现其光谱特征提取,所提取光谱数大多在10条以上,这使得油水两相测量光纤式传感器的制造成本很高且工程实现难度很大。为提高基于光谱分析的油水两相测量光纤式传感器的实用性,需要实现油水两相红外光谱的超稀疏表示。为此提出了油水混合物光谱自-互相关联合(self-cross correlation,SCC)的光谱超稀疏表示方法。为了验证方法的有效性,搭建了油水混合物红外光谱含水率测量实验装置,从SCC算法筛选出的6个波段中,根据实际生产工艺选择了1 050 nm和1 650 nm波段进行动态实验,实验结果表明,1 050 nm和1 650 nm波段对油和水的混合流型响应良好,且两者呈现出了显著的互相关性。显然,本文研究有助于提升工业光纤式传感器的使用性能。     

Measurement of velocity of sand-containing Oil–Water two-phase flow with super high water holdup in horizontal small pipe based on thermal tracers

When oil fields enter the last production period, the water holdup in the well is extremely high. Chemical flooding and horizontal well technology are often used to enhance oil recovery. These techniques result in a high downhole fluid viscosity and serious sand production, which leads to the failure of common velocity measurements because of sticking sand, and yields new logging difficulties. This paper presents a method of the velocity measurement of sand-containing oil–water two-phase flow in a super high water holdup pipe diameter based on thermal tracers. The measurement accuracy of the thermal tracer velocity method is related closely to parameters that affect its performance. Parameter optimization is required to improve the measurement accuracy. ANSYS Fluent was used for a numerical simulation of the heat-source shape and material, thermistor probe installation position and fluid heating power, and the method was verified experimentally. The optimal parameters of the thermal tracer flowmeter were obtained by numerical simulation, the heat source material was aluminum and the shape was rectangular. The thermistor probe was located 160–220 mm from the heat source, and the pulse heating power was 350 W. The experiment results show that the accuracy of the thermal tracer flowmeter was 4%, the repeatability was 2.6%, and the measurement accuracy of the flow velocity was unaffected by water holdup and sand.     

光纤持气率测井仪响应规律的实验研究

为考察现有光纤持气率计在油气水三相流中的响应特性,采用多相流标定装置对其进行测定,系统研究光纤持气率计在油量固定不变含水量不同条件下的持气率响应规律。实验结果表明,当油量为5m3/d、气量小于10m3/d时,持气率随含气量的增大而增大,二者线性变化程度较低;而气量在10～35m3/d之间变化时,持气率随含气量的增大而线性增大。     

Design of a Conductance and Capacitance Combination Sensor for water holdup measurement in oil–water two-phase flow

Oil–water two-phase flow widely exists in the process of petroleum industry. The liquid holdup measurement in horizontal pipeline is very important and difficult. In this work, a Conductance and Capacitance Combination Sensor (CCCS) system with four conductance rings and two concave capacitance plates is designed and validated for its measurement performance of in situ water holdup through dynamic experiments. A set of fast electronic switches controls the conductance rings and the capacitance plates alternatively set up each own sensing field in the same sensing volume. This configuration ensures the water holdup estimation in the range from 0% to 100% regardless of flow direction. A set of quick closing valves was used to acquire the in situ holdup for the on-line calibration of the CCCS system. The theoretical correlations of conductance sensor and capacitance sensor were established to make the real-time measurement convenient. A real-time measurement method by CCCS system is provided based on the fusion of the conductance and the capacitance measurement without flow pattern recognition. This method delivers an average error of 1.06% for the CCCS system measuring the water holdup of oil–water two-phase flow, with a standard deviation of 0.038 and a relative error less than ±5%.     

石油生产光纤-电导组合探针阵列多分相测井仪研究

为解决石油生产多分相测量问题,基于课题组研制的创新型光纤-电导组合探针设计研制一种用于石油生产多参数测量的高精度、高灵敏度探测仪器。采用ZEMAX光线追迹方法和FEM数值分析方法对光纤-电导组合探针阵列多分相测井仪电场分布、响应特性进行了理论分析,且验证了其在流量为5、10、20、30 m~3/d,持气率为10%、20%、30%、40%,持水率为90%、80%、70%、60%等工况下良好的测量效果。为进一步证明其优良性能,以液相流量30 m~3/d,液相持水率25%、45%、65%及85%,气流量6、12、24 m~3/d等多相流工况为例进行动态实验分析,其持气率测量误差在5%以内,持水率误差在10%以内。实际动态实验与仿真模拟结果保持相同。充分表明光纤-电导组合探针阵列多分相测井仪的良好的性能。     

A parallel-wire microwave resonant sensor for measurement of water holdup in high water-cut oil-in-water flows

In the present study, we propose a parallel-wire microwave resonant sensor (PMRS) with transmission-through configuration for water holdup measurement in high water-cut oil-in-water flows. Through the finite element method (FEM) analysis using HFSS software, the variations of sensor responses for changing water holdup and salinity are investigated. In this manner, the optimum working frequency of microwave resonant sensor is tuned to 1.8 GHz. With the designed PMRS measurement system, an experimental test of vertical high water-cut oil-in-water flows is conducted in a 20 mm inner diameter pipe, through which the relationship among dimensionless normalized phase output of PMRS which reflects the water holdup information, water-cut and total flow rate are investigated. The results show that PMRS presents a high resolution in measurement of water holdup. By establishing statistics models, water-cut can be accurately predicted. Besides, PMRS can still retain high resolution under the circumstance of high salinity. To conclude, PMRS can possess high resolution in measurement of water holdup with both high water-cut and salinity variation in oil-in-water flows, and satisfactory water-cut measurement results can be achieved.     

A flow rate measurement method for horizontal oil-gas-water three-phase flows based on Venturi meter,blind tee,and gamma-ray attenuation

Online horizontal oil-gas-water three-phase flow rate monitoring is essential for reliable operations during industrial production. A flow rate measurement method is developed in horizontal oil-gas-water three-phase flows by combining a blind tee, a Venturi meter, and a gamma-ray densitometer. The blind tee is installed at the test section entrance to homogenize the mixture by transforming the horizontal flow to a vertical upward flow. The Venturi meter is used for the total flow rate measurement. The dual-energy gamma-ray densitometer is used for phase holdup measurement. In the present method, blind-tee mixing effects and oil-water mixture slip behavior is essential, which were experimentally analyzed in this work. The phase inversion was found in the oil-water mixture with the increasing of the oil volume fraction. Besides, the addition of the gas reduces the oil-water slip ratio. For the range of 0–35% and 65–100% oil fraction in the oil-water liquid, the oil-water mixture can be well treated as a pseudo homogenous liquid with a slip ratio of 0.9–1.1. A three-phase flow rate model is then established for these conditions. The method was validated by horizontal oil-gas-water three-phase flows with average relative errors of 3.2% for the total flow rates, 4.3% for the gas flow rates, 11.5% for the oil flow rates, and 7.8% for the water flow rates.     

A theoretical model for a capacitance tool and its application to production logging

A new theoretical model for a capacitance sensor used for measuring water holdup in production logging is proposed in this paper. The model realizes that the capacitance sensor is sensitive to oil droplets that collide against the sensor's inner electrode coated with an insulator when the water is electrically conductive and is the continuous phase in an oil/water bubbly flow. The sensor still has the ability to distinguish between oil and water in this case, its sensitivity decreasing with fluid velocity. The experiments were performed in a multiphase flow loop, and the results strongly confirm the theory. On the basis of the model, the measuring principle of the sampling-type capacitance tool is discussed, and an attempt to evaluate average oil droplet size with the capacitance sensor in the case of oil in water is also made.