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CFD-Aided Investigation of Combined Flow Conditioners for Gas Ultrasonic Flow Meter
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作者 袁亚琦 李世阳 +1 位作者 郑佳 李明睿 《Journal of Shanghai Jiaotong university(Science)》 EI 2023年第5期611-620,共10页
Stable and fully developed gas flow field is crucial for realizing accurate measurement of gas ultrasonicflow meter. To reduce the flow field distortion, a flow conditioner is usually used. However, the traditionalmon... Stable and fully developed gas flow field is crucial for realizing accurate measurement of gas ultrasonicflow meter. To reduce the flow field distortion, a flow conditioner is usually used. However, the traditionalmonotype flow conditioner can only improve the flow field distribution partly. The measurement accuracy of thetransit time ultrasonic flow meter is still affected because of its serious flow field distortion in the complex pipelineconditions. In this paper, to further improve the flow field distribution, a combined conditioner is investigated.The combined flow conditioner is composed of fan-shaped section, turbulent mixing cavity, and honeycomb-shapedsection. The effects of fan blade angle and cavity length on the flow field of the DN50 flow meter are studied usingcomputational fluid dynamics (CFD) simulation. Simulation results indicate that compared with the monotypeconditioner, the combined conditioner has better performance on effectively reducing the swirl and turbulence andproviding more stable and repetitive velocity profiles. Experiments also validate the effectiveness of the combinedconditioner. The flow meter with the combined conditioner has better repeatability of less than 0.2%, which isbetter than those of the monotype conditioners under the same conditions. This work is very useful for accuratemeasurement of gas ultrasonic flow meter, especially for the complex pipeline conditions. 展开更多
关键词 computational fluid dynamics(CFD) flow conditioners gas ultrasonic flow meter SWIRL TURBULENCE
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Generation of Arbitrary Pressure Pulsation of Wide Frequency Range for Flow Meter Testing in a Laminar Gas Pipeline 被引量:1
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作者 Mitsuhiro Nakao Tomonori Kato +2 位作者 Takashi Oowaku Hirohisa Sakuma Toshiharu Kagawa 《Journal of Flow Control, Measurement & Visualization》 2014年第4期125-137,共13页
The present paper presents a device to test flow meters under an arbitrary pressure pulsation in a gas pipeline with a laminar flow containing frequency components up to 50 Hz, with the amplitude reaching hundreds of ... The present paper presents a device to test flow meters under an arbitrary pressure pulsation in a gas pipeline with a laminar flow containing frequency components up to 50 Hz, with the amplitude reaching hundreds of pascals. In order to reduce flow noise, the device has a strainer-like element connected to a pipeline under test and uses an open-loop control law based on the frequency response test. The control signal is calculated by adding the inputs to obtain each of the sinusoidal waves included in the original wave, which was decomposed by Fourier analysis. The validity of the developed method is demonstrated through the generation tests of superimposed pressure waves containing frequency components up to 50 Hz. Analysis of the relative uncertainty demonstrated the relative uncertainty to be less than 10% when the generated pressure is larger than 360 Pa. 展开更多
关键词 UNSTEADY flow flow meter Linear WAVE Superimposed WAVE PNEUMATICS
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Computer Aided Design of Differential Pressure Flow Meters
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作者 Yevhen Pistun Leonid Lesovoy +1 位作者 Fedir Matiko Roman Fedoryshyn 《World Journal of Engineering and Technology》 2014年第2期82-91,共10页
New methodology of designing the differential pressure flow meters for fluid energy carriers is developed in order to provide minimum uncertainty of results of flow rate measurement. This methodology is implemented in... New methodology of designing the differential pressure flow meters for fluid energy carriers is developed in order to provide minimum uncertainty of results of flow rate measurement. This methodology is implemented in “Raskhod-RU” CAD system for computer aided design and calculation of differential pressure flow meters. “Raskhod-RU” CAD meets the requirements of new Standards implemented in CIS countries (GOST 8.586.1,2,3,4,5-2005) and provides accomplishment of the following tasks: verification of conditions (constraints) for application of the differential pressure method according to the requirements of new Standards;calculation of parameters of primary device, pipe straight lengths and flow meter in general according to the requirements of new Standards;calculation of uncertainty of results of fluid flow rate and volume measurement. 展开更多
关键词 flow meter DESIGN UNCERTAINTY OPTIMIZATION Requirements
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Measurement of oil-water flow via the correlation of turbine flow meter, gamma ray densitometry and drift-flux model 被引量:4
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作者 李东晖 许晶禹 《Journal of Hydrodynamics》 SCIE EI CSCD 2015年第4期548-555,共8页
The flow rate of the oil-water horizontal flow is measured by the combination of the turbine flow meter and the singlebeam gamma ray densitometry. The emphasis is placed on the effects of the pipe diameter, the oil vi... The flow rate of the oil-water horizontal flow is measured by the combination of the turbine flow meter and the singlebeam gamma ray densitometry. The emphasis is placed on the effects of the pipe diameter, the oil viscosity and the slip velocity on the measurement accuracy. It is shown that the mixture flow rate measured by the turbine flow meter can meet the application requirement in the water continuous pattern( o- w flow pattern). In addition, by introducing the developed drift-flux model into the measurement system, the relative errors of measurements for component phase flow rates can be controlled within ±5%. Although more accurate methods for the flow rate measurement are available, the method suggested in this work is advantageous over other methods due to its simplicity for practical applications in the petroleum industry. 展开更多
关键词 oil and water flow flow rate measurement turbine flow meter gamma ray densitometry drift-flux model
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MEASUREMENT OF SOLID SLURRY FLOW VIA CORRELATION OF ELECTROMAGNETIC FLOW METER,ELECTRICAL RESISTANCE TOMOGRAPHY AND MECHANISTIC MODELLING 被引量:3
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作者 XU Jing-yu WU Ying-xiang +5 位作者 ZHENG Zhi-chu WANG M. MUNIR B. OLUWADAREY H. I. SCHLABERG H. I. WILLIAMS R. A. 《Journal of Hydrodynamics》 SCIE EI CSCD 2009年第4期557-563,共7页
The study presented here was carried out to obtain the actual solids flow rate by the combination of electrical resistance tomography and electromagnetic flow meter. A new in-situ measurement method based on measureme... The study presented here was carried out to obtain the actual solids flow rate by the combination of electrical resistance tomography and electromagnetic flow meter. A new in-situ measurement method based on measurements of the Electromagnetic Flow Meters (EFM) and Electrical Resistance Tomography (ERT) to study the flow rates of individual phases in a vertical flow was proposed. The study was based on laboratory experiments that were carded out with a 50 mm vertical flow rig for a number of sand concentrations and different mixture velocities. A range of sand slurries with median particle size from 212 μm to 355 μm was tested. The solid concentration by volume covered was 5% and 15%, and the corresponding density of 5% was 1078 kg/m^3 and of 15% was 1238 kg/m^3. The flow velocity was between 1.5 m/s and 3.0 m/s. A total of 6 experimental tests were conducted. The equivalent liquid model was adopted to validate in-situ volumetric solids fraction and calculate the slip velocity. The results show that the ERT technique can be used in conjunction with an electromagnetic flow meter as a way of measurement of slurry flow rate in a vertical pipe flow. However it should be emphasized that the EFM results must be treated with reservation when the flow pattern at the EFM mounting position is a non-homogenous flow. The flow rate obtained by the EFM should be corrected considering the slip velocity and the flow pattern. 展开更多
关键词 slurry measurement Electrical Resistance Tomography (ERT) Electromagnetic flow meters (EFM) in-situ mean volumetric fraction slip velocity
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Prediction of oil flow rate through an orifice flow meter: Artificial intelligence alternatives compared
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作者 Hamzeh Ghorbani David A.Wood +4 位作者 Abouzar Choubineh Afshin Tatar Pejman Ghazaeipour Abarghoyi Mohammad Madani Nima Mohamadian 《Petroleum》 CSCD 2020年第4期404-414,共11页
Fluid-flow measurements of petroleum can be performed using a variety of equipment such as orifice meters and wellhead chokes.It is useful to understand the relationship between flow rate through orifice meters(Qv)and... Fluid-flow measurements of petroleum can be performed using a variety of equipment such as orifice meters and wellhead chokes.It is useful to understand the relationship between flow rate through orifice meters(Qv)and the five fluid-flow influencing input variables:pressure(P),temperature(T),viscosity(μ),square root of differential pressure(ΔP^0.5),and oil specific gravity(SG).Here we evaluate these relationships using a range of machine-learning algorithms applied to orifice meter data from a pipeline flowing from the Cheshmeh Khosh Iranian oil field.Correlation coefficients indicate that(Qv)has weak to moderate positive correlations with T,P,andμ,a strong positive correlation with theΔP^0.5,and a weak negative correlation with oil specific gravity.In order to predict the flow rate with reliable accuracy,five machine-learning algorithms are applied to a dataset of 1037 data records(830 used for algorithm training;207 used for testing)with the full input variable values for the data set provided.The algorithms evaluated are:Adaptive Neuro Fuzzy Inference System(ANFIS),Least Squares Support Vector Machine(LSSVM),Radial Basis Function(RBF),Multilayer Perceptron(MLP),and Gene expression programming(GEP).The prediction performance analysis reveals that all of the applied methods provide predictions at acceptable levels of accuracy.The MLP algorithm achieves the most accurate predictions of orifice meter flow rates for the dataset studied.GEP and RBF also achieve high levels of accuracy.ANFIS and LSSVM perform less well,particularly in the lower flow rate range(i.e.,<40,000 stb/day).Some machine learning algorithms have the potential to overcome the limitations of idealized streamline analysis applying the Bernoulli equation when predicting flow rate across an orifice meter,particularly at low flow rates and in turbulent flow conditions.Further studies on additional datasets are required to confirm this. 展开更多
关键词 Orifice flow meters flow-rate-predicting virtual meters Multiple machine-learning algorithm comparisons Metrics influencing oil flow flow-rate prediction error analysis
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Application of EEMD combined with cross-correlation algorithm in Doppler flow signal 被引量:1
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作者 SHI Fengdong GONG Ruishi +1 位作者 LIANG Tongtong LÜDong 《Journal of Measurement Science and Instrumentation》 2025年第1期58-65,共8页
To address the issue of low measurement accuracy caused by noise interference in the acquisition of low fluid flow rate signals with ultrasonic Doppler flow meters,a novel signal processing algorithm that combines ens... To address the issue of low measurement accuracy caused by noise interference in the acquisition of low fluid flow rate signals with ultrasonic Doppler flow meters,a novel signal processing algorithm that combines ensemble empirical mode decomposition(EEMD)and cross-correlation algorithm was proposed.Firstly,a fast Fourier transform(FFT)spectrum analysis was utilized to ascertain the frequency range of the signal.Secondly,data acquisition was conducted at an appropriate sampling frequency,and the acquired Doppler flow rate signal was then decomposed into a series of intrinsic mode functions(IMFs)by EEMD.Subsequently,these decomposed IMFs were recombined based on their energy entropy,and then the noise of the recombined Doppler flow rate signal was removed by cross-correlation filtering.Finally,an ideal ultrasonic Doppler flow rate signal was extracted.Simulation and experimental verification show that the proposed Doppler flow signal processing method can effectively enhance the signal-to-noise ratio(SNR)and extend the lower limit of measurement of the ultrasonic Doppler flow meter. 展开更多
关键词 ultrasonic Doppler flow meter ensemble empirical mode decomposition(EEMD) CROSS-CORRELATION fast Fourier transform(FFT)spectrum analysis energy entropy
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Vacuum and Air Flow for 2QXP-1 Vacuum Precision Seed Metering
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作者 Su Wei Wang Fu-lin +1 位作者 Chen Hai-tao Lai Qing-hui 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第2期61-64,共4页
Vacuum precision seed metering is the key part of vacuum seed planter. Planting performance of planter is affected by vacuum and air flow which are important parameters for choosing fan. Effects of qualification perce... Vacuum precision seed metering is the key part of vacuum seed planter. Planting performance of planter is affected by vacuum and air flow which are important parameters for choosing fan. Effects of qualification percent and miss percent on air chamber vacuum 3, 4, 5 and 6 kPa were studied at different operating speeds. The results showed that operating performance of the seed metering was excellent when air chamber vacuum was 5 and 6 kPa, which air flow was 7.4-8.0 m3·s-1 and 8.0-8.8 m3·s-1 , respectively. 展开更多
关键词 seed planter precision seed metering vacuum degree air flow
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Su-6 Well Obtaining Industrial Gas Flow of More Than 1 Million Cubic Meters
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《China Oil & Gas》 CAS 2000年第3期30-32,共3页
关键词 flow Su-6 Well Obtaining Industrial Gas flow of More Than 1 Million Cubic meters OO
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皂膜流量计计量时湿度修正研究
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作者 刘慧平 羊亚坤 +2 位作者 钟俊杰 杨国吉 李向召 《计量与测试技术》 2026年第1期19-22,共4页
本文基于皂膜流量计在计量过程中气路的湿度,研究其与流量大小、测量时间的关系,并结合实验数据,得到修正公式,从而确保该流量计量值溯源的准确性。
关键词 电池隔膜 透气度 透气体积 皂膜流量计
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Methodology for production logging in oil-in-water flows under low flow rate and high water-cut conditions 被引量:2
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作者 Wang Da-Yang Jin Ning-De +2 位作者 Zhai Lu-Sheng Ren Ying-Yu He Yuan-Sheng 《Applied Geophysics》 SCIE CSCD 2019年第3期302-313,395,共13页
This study aimed to obtain the production profiles of oil-in-water flow under low flow rate and high water-cut conditions in oil wells.A combination production profile logging composed of an arc-type conductance senso... This study aimed to obtain the production profiles of oil-in-water flow under low flow rate and high water-cut conditions in oil wells.A combination production profile logging composed of an arc-type conductance sensor(ATCS)and a cross-correlation flow meter(CFM)with a center body is proposed and experimentally evaluated.The ATCS is designed for water holdup measurement,whereas the CFM with a center body is proposed to obtain the mixture velocity.Then,a drift-flux model based on flow patterns is established to predict the individual-phase superficial velocity of oil-in-water flows.Results show that the ATCS possesses high resolution in water holdup measurement and that flow pattern information can be deduced from its signal through nonlinear time series analysis.The CFM can enhance the correlation of upstream and downstream signals and simplify the relationship between the cross-correlation velocity and mixture velocity.On the basis of the drift-flux model,individual-phase superficial velocities can be predicted with high accuracy for different flow patterns. 展开更多
关键词 oil-in-water flows low flow rate high water-cut conductance sensor flow meter measurement model
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AutoFlow在定容控制通气模式中的应用 被引量:1
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作者 黄捷晖 张艳 +3 位作者 赵新国 徐洪杰 储美萍 徐晔 《临床肺科杂志》 2013年第11期1943-1944,共2页
目的探讨AutoFlow(自动变流)在机械通气定容控制通气模式中对患者气道压力和血液动力学的影响。方法 71例接受机械通气的患者随机分为观察组(SIMV-PSV-PEEP+AutoFlow)和对照组(SIMV-PSV-PEEP),采集相关数据进行统计学分析比较。结果在SI... 目的探讨AutoFlow(自动变流)在机械通气定容控制通气模式中对患者气道压力和血液动力学的影响。方法 71例接受机械通气的患者随机分为观察组(SIMV-PSV-PEEP+AutoFlow)和对照组(SIMV-PSV-PEEP),采集相关数据进行统计学分析比较。结果在SIMV-PSV方式基础上加用AutoFlow,能显著降低气道吸气峰压(PIP)和气道平均压(Pmean),气道阻力(R)有减小,差异有显著性;观察组和对照组患者的血流动力学监测结果差异无显著性。结论 SIMV定容控制通气模式联合AutoFlow既可以保证潮气量又避免气道压过高,对血液动力学影响不大。 展开更多
关键词 AUTOflow 机械通气 定容型 气道压 血液动力学
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基于机理和数据耦合方法的实时油气井产量测量算法的研究
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作者 李金蔓 林杨 +5 位作者 安创锋 刘艺萌 肖天昊 黑梦丽 亓佳宁 宫敬 《油气田地面工程》 2026年第1期66-73,共8页
随着数字化和智能化的发展,虚拟计量技术(VFM)逐渐成为解决油气田开发与生产中多相流量计高成本和低可靠性问题的重要替代方案。结合机理模型和传统数据驱动模型,研究了虚拟计量技术在油气井生产实时测量中的应用。首先,对南海凝析气田... 随着数字化和智能化的发展,虚拟计量技术(VFM)逐渐成为解决油气田开发与生产中多相流量计高成本和低可靠性问题的重要替代方案。结合机理模型和传统数据驱动模型,研究了虚拟计量技术在油气井生产实时测量中的应用。首先,对南海凝析气田的数据进行数据预处理,包括数据清洗、标准化、特征工程等。然后,结合虚拟计量机理模型的知识,基于节点分析的原理,建立了分段流量预测模型,并与传统的数据驱动模型进行比较,研究不同模型的预测性能。结果表明,此研究建立的分段流量预测模型的平均相对误差最小,A1井的平均相对误差为0.183%,A2井的平均相对误差为0.108%,有效地捕获了数据之间的关系。此研究促进了虚拟计量技术在油气井产量实时测量中的应用,提高了生产系统的监测水平。 展开更多
关键词 油气井生产 虚拟计量 混合模型 分段流量预测模型
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基于改善流动特性的超声波水表全局优化设计方法
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作者 廖虎 徐栋义 +2 位作者 胡余平 胡善良 黄国华 《仪表技术与传感器》 北大核心 2026年第3期42-49,共8页
为提高超声波水表内流动稳定性、减少压力损失,提出一种基于改善流动特性的优化设计方法。利用CFD仿真计算方法,对超声波水表DN15型基表进行内部流场分析,定位流动缺陷位置并分析产生原因,有针对性地进行优化迭代设计:将进口反射片由片... 为提高超声波水表内流动稳定性、减少压力损失,提出一种基于改善流动特性的优化设计方法。利用CFD仿真计算方法,对超声波水表DN15型基表进行内部流场分析,定位流动缺陷位置并分析产生原因,有针对性地进行优化迭代设计:将进口反射片由片状改为流线状,有利于引流从而消减反射片背部涡旋及后方离散涡旋,提高流动稳定性;增加缩颈段直径及圆弧过渡,减少压力损失,减少因形状扩张产生的阶梯角涡;沿流动分离线设计出口反射片形状,促使流动贴合、延迟流动分离。对比基表优化前后的计算结果,大流量下流动稳定性提高61.4%,全流量段压力损失减少33.3%~70.9%。 展开更多
关键词 超声波水表 流动稳定性 压力损失 优化设计 数值计算
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油品管输流量计的主要类型及其影响因素
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作者 苏灵杰 《广州化工》 2026年第2期158-161,共4页
随着全球能源需求的持续增长和油品输送规模的不断扩大,管输流量计在油品输送系统中的重要性日益突显。流量计作为油品管输系统中的核心计量设备,不仅承担着精确测量油品流量的关键任务,更是实现计费结算、运行监控和系统高效操作的基... 随着全球能源需求的持续增长和油品输送规模的不断扩大,管输流量计在油品输送系统中的重要性日益突显。流量计作为油品管输系统中的核心计量设备,不仅承担着精确测量油品流量的关键任务,更是实现计费结算、运行监控和系统高效操作的基础。考虑到油品管输流量计的精确性直接影响着能源计量和经济效益,本文就油品管输流量计的主要类型及其影响因素进行了探究,介绍了油品管输流量计主要类型,探讨了外在因素对流量计精准的影响因素,重点探讨科里奥利质量流量计的组成及其原理环境温度变化外在因素对流量计测量精度的影响机制,提出了保障油品管输流量计准确性的建议,以期为相关从业人员提供有价值的参考,促进油品管输系统计量水平的提升。 展开更多
关键词 管输流量计 性能比较 影响因素
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流出系数干扰下差压式流量计智能校准方法
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作者 周文辉 冯鑫 《计算机仿真》 2026年第2期330-333,339,共5页
流出系数受到多种因素综合影响,这些因素相互交织,增加了确定流出系数准确值的难度,进而影响智能校准方法的准确性。对此,研究流出系数干扰下差压式流量计智能校准方法。首先,阐述流出系数干扰对差压式流量计测量结果的影响,通过伯努利... 流出系数受到多种因素综合影响,这些因素相互交织,增加了确定流出系数准确值的难度,进而影响智能校准方法的准确性。对此,研究流出系数干扰下差压式流量计智能校准方法。首先,阐述流出系数干扰对差压式流量计测量结果的影响,通过伯努利方程和流动连续性方程推导出实际测量流量,并计算示值误差。然后,针对增量式PID控制算法在复杂状况下确定最优控制参数的局限性,引入人群搜索算法(SOA)对其控制参数进行优化。最后,将示值误差作为改进增量式PID的输入,输出差压控制信号,实现对差压式流量计的校准。实验证明:上述方法可有效确定差压式流量计的流出系数,计算得到实际测量流量;可有效控制流出系数干扰下差压式流量计的差压信号,完成智能校准。 展开更多
关键词 流出系数干扰 差压式 流量计 智能校准 人群搜索算法
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船用LNG计量系统关键技术研究与应用
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作者 秦克胜 杨朋飞 于晓辉 《山东化工》 2026年第3期200-203,共4页
随着我国经济的快速增长和能源结构的优化,天然气需求日益增加,LNG(液化天然气)燃料因可减少90%硫氧化物、25%二氧化碳排放,成为世界完成“双碳”目标的重要能源。LNG船作为运输LNG载体,其需求量也大大增加,国内LNG船设计与建造技术逐... 随着我国经济的快速增长和能源结构的优化,天然气需求日益增加,LNG(液化天然气)燃料因可减少90%硫氧化物、25%二氧化碳排放,成为世界完成“双碳”目标的重要能源。LNG船作为运输LNG载体,其需求量也大大增加,国内LNG船设计与建造技术逐步成熟,但LNG船上的部分核心设备,例如船用LNG计量系统作为天然气贸易结算与控制的关键,一直是国产化进程中急需突破的领域。依托中海油科技项目课题,开展船用计量系统关键技术包括船用LNG计量橇工艺流程、重点仪表如流量计和分析仪选型、船用LNG计量橇自动化工程设计研究。最终制造一套计量橇样机,完成工厂出厂测试,达到贸易交接精度要求,这是摆脱船用LNG计量系统国外技术封锁的重要举措,具有重要的现实意义。 展开更多
关键词 LNG船 计量系统 科里奥利质量流量计 色谱分析仪
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高精度自动气体流量计检定装置的设计与实现
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作者 廖建文 钱康亮 《自动化应用》 2026年第4期134-139,共6页
设计并实现了一套基于主动旋转鼓轮原理的新型气体流量计检定装置,旨在为流量计量领域提供高精度、高效率的检定方案。装置的核心思想是,通过高精度伺服控制系统主动驱动一个功能等效的“液封式活塞”(即内部精密构造的湿式鼓轮)进行精... 设计并实现了一套基于主动旋转鼓轮原理的新型气体流量计检定装置,旨在为流量计量领域提供高精度、高效率的检定方案。装置的核心思想是,通过高精度伺服控制系统主动驱动一个功能等效的“液封式活塞”(即内部精密构造的湿式鼓轮)进行精密旋转,直接生成可溯源至几何尺寸的标准体积流量。系统性地论述了该装置的设计理念、关键技术方案及实现细节,重点探讨了其在提高检定效率和精度方面的创新技术,包括基于“逐位移元”的动态误差补偿模型、高动态响应的伺服流量控制策略以及基于概率框架的视觉自动识别系统。详尽的实验结果表明,该装置的扩展不确定度优于0.15%(k=2),重复性优于0.05%,检定效率较传统钟罩法提升70%以上,实现了全流程的高度自动化检定,综合性能达到行业领先水平。 展开更多
关键词 主动活塞 气体流量计 智能检定 自动控制 湿式鼓轮
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气体超声流量计内置整流器优化设计
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作者 林时锋 柯明华 李逢春 《自动化与仪表》 2026年第1期111-114,共4页
针对天然气计量中弯管扰流造成气体超声流量计流场畸变的难题,基于蜂窝剪切-稳流腔耗散耦合机理,提出一种三级双稳流腔内置蜂窝整流器。通过优化三级整流器结构参数,实现多级孔径协同与稳流腔缓冲作用。经CFD数值仿真与实流标定双重验证... 针对天然气计量中弯管扰流造成气体超声流量计流场畸变的难题,基于蜂窝剪切-稳流腔耗散耦合机理,提出一种三级双稳流腔内置蜂窝整流器。通过优化三级整流器结构参数,实现多级孔径协同与稳流腔缓冲作用。经CFD数值仿真与实流标定双重验证,整流后速度剖面均匀度显著提升,测量误差、重复性满足国标要求,该装置为受限安装条件下超声流量计的高精度、高可靠性应用提供了工程可行的创新路径。 展开更多
关键词 气体超声流量计 内置整流器 CFD数值仿真
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热成像技术在视频图像河段流速监测中的应用研究
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作者 蔡钊 廖敏涵 +3 位作者 刘九夫 刘宏伟 储少志 闵星 《水电能源科学》 北大核心 2026年第1期11-14,共4页
视频图像流速监测技术在水文监测、灌区监测中已有一定的应用,但由于受到光的限制,视频图像流速监测在夜晚和低光照条件下的监测存在局限性。为此,利用热成像增加视频测流的光谱适用范围,弥补视频测流在夜晚条件适用性不高的缺点,通过... 视频图像流速监测技术在水文监测、灌区监测中已有一定的应用,但由于受到光的限制,视频图像流速监测在夜晚和低光照条件下的监测存在局限性。为此,利用热成像增加视频测流的光谱适用范围,弥补视频测流在夜晚条件适用性不高的缺点,通过无人机搭载可见光和热成像双面摄像装置,对比了可见光条件下和夜晚条件下可见光和热成像摄像装置的流速场反演结果与流速仪监测数据。结果表明,在白天可见光充足条件下,使用可见光视频图像流速反演的效果较好,除去个别点监测精度误差可达到-5%以内;热成像相机由于自身分辨率的限制,对河道水面天然示踪物有一定的捕获能力,具有河道表面流速场的反演能力和潜力,若在河段中加入冷冰块失踪粒子,可明显提高热成像在夜间的监测精度,除去1个点监测精度的相对误差为8.4%外,其他3个点的精度较高,均在-1%左右。研究结果为提高视频测流在夜间和光照低条件下的监测精度提供了重要参考。 展开更多
关键词 视频测流 大尺度粒子图像测速 热成像 流速仪
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