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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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Application of EEMD combined with cross-correlation algorithm in Doppler flow signal
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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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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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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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基于空气标定的热式流量仪表研制与应用 被引量:1
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作者 刘华成 孙偲 +1 位作者 韩少云 张磊 《传感器与微系统》 北大核心 2025年第5期164-168,共5页
热式流量仪表信号源于发热探头与介质之间的热交换量,在同一流速场下受介质类型影响,而国内标定装置的介质一般为空气。为解决热式流量仪表在非空气介质管路中流量测量精度低的问题,从热扩散原理出发,研制了一种基于空气标定的热式流量... 热式流量仪表信号源于发热探头与介质之间的热交换量,在同一流速场下受介质类型影响,而国内标定装置的介质一般为空气。为解决热式流量仪表在非空气介质管路中流量测量精度低的问题,从热扩散原理出发,研制了一种基于空气标定的热式流量仪表,并采用多项式拟合算法对仪表标定数据进行拟合,同时,通过对原理中涉及介质传热的比热容cp、导热系数k等参量进行分析,得到传热特性差异,提出了一种在不同介质工况应用中的信号修正方法,并将修正算法应用到仪表中。本文验证了常温常压空气标定的精度,满足1.0级精度要求,量程比达100!1,并搭建了不同介质的试验平台,将空气标定的仪表在氩气介质条件下开展应用测试。测试结果表明:通过对信号补偿,仪表输出精度显著提升,满足1.5级精度要求。本文方法可有效解决特定空间内非空气流量测量精度低的问题,对于扩大本仪表使用范围及精准测量目标场所气体流量等具有实际应用价值。 展开更多
关键词 热式流量仪表 热扩散原理 多项式拟合 介质传热
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夏热冬暖和夏热冬冷地区典型多联机空调系统性能测试与对比分析
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作者 张辉 强文博 +2 位作者 彭晨玮 杨松燃 魏庆芃 《暖通空调》 2025年第9期28-36,共9页
多联机空调系统作为居住建筑、小型公共建筑中常见的空调形式,常常被认为具备灵活可调、运行高效等独特优势,在国内外中小型商用建筑及部分大型办公和居住建筑中得到了广泛应用。然而,多联机空调系统在实际应用中也逐渐暴露出一些急需... 多联机空调系统作为居住建筑、小型公共建筑中常见的空调形式,常常被认为具备灵活可调、运行高效等独特优势,在国内外中小型商用建筑及部分大型办公和居住建筑中得到了广泛应用。然而,多联机空调系统在实际应用中也逐渐暴露出一些急需解决的痛点问题。本研究选取了位于我国夏热冬暖地区和夏热冬冷地区的2座使用中的办公建筑,采用制冷剂质量流量计法、压缩机性能曲线法和空气焓差法对2套多联机空调系统进行了现场实测。结果表明,实验室条件下表现良好的多联机空调系统在实际运行中的能效与预期存在一定的差异,设备选型过大问题会直接导致系统长时间在低负荷率下运行,不仅增加了制冷剂充注量,提高了泄漏风险,并导致部分负荷下多联机系统能耗并未显著降低。此外,用户对室内机的分散控制可能导致运行不合理,进一步影响系统能效,急需针对多联机空调系统进行节能调适。 展开更多
关键词 多联机空调系统 实测研究 制冷系统 运行能效 办公建筑 制冷剂质量流量计法 压缩机性能曲线法 空气焓差法
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入口压力及系统压差对气体输送系统流量的影响 被引量:2
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作者 汪涵 朱春英 +1 位作者 马友光 付涛涛 《化工学报》 北大核心 2025年第2期596-611,共16页
使用气体输送系统进行实验过程中时常会出现实际流量发生偏差的现象,并且不同入口压力和系统压差下其偏差值大小不同,一定情况下会影响实验结果的准确性,可通过误差预测对实验结果进行修正。以氮气输送系统为例,通过改变入口压力、压差... 使用气体输送系统进行实验过程中时常会出现实际流量发生偏差的现象,并且不同入口压力和系统压差下其偏差值大小不同,一定情况下会影响实验结果的准确性,可通过误差预测对实验结果进行修正。以氮气输送系统为例,通过改变入口压力、压差和流量大小与范围并测量实际流量,进行误差分析和预测。研究结果表明,系统压差对流量控制的影响较小,而入口压力的增大需要配合背压阀的使用从而提高系统的精度,因此可以增加入口压力使偏差值更小。同时,根据理论推导和实验结果提出了普适的误差值与流量值的预测模型,可准确预测实际流量,为气体输送系统的误差分析与精准控制提供了新思路。 展开更多
关键词 气体 气力输送 测量 质量流量计 误差分析 流量控制
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非金属矿山地表河流渗漏水综合探测技术研究 被引量:1
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作者 唐澳柔 张义平 朱华杰 《中国矿业》 北大核心 2025年第4期234-240,共7页
非金属矿山地表河流渗漏水会对矿山安全造成影响,工程上常使用物理探测方法来判定渗漏水河段的大致位置,但单一物探方法定位误差较大。为解决定位误差较大的问题,本文以贵州某磷矿渗漏水河段为研究对象,拟采用流量断面法与探地雷达法对... 非金属矿山地表河流渗漏水会对矿山安全造成影响,工程上常使用物理探测方法来判定渗漏水河段的大致位置,但单一物探方法定位误差较大。为解决定位误差较大的问题,本文以贵州某磷矿渗漏水河段为研究对象,拟采用流量断面法与探地雷达法对渗漏水河段进行综合探测。结果表明,根据LS300-A流速仪测量结果得出洋水河不同河段渗漏情况:大石头上游到大石头下游的渗透能力最强,涵洞(一)出口至地下水环境监测井段次之,炸药库到炸药库下游最弱;使用探地雷达判定渗漏河段不良地质体分布位置,由地质雷达图像异常区域分析得出各渗漏水河段均有裂隙带发育,其中,涵洞(一)出口至地下水环境监测井段裂隙发育程度高于炸药库上下游发育程度。相较于传统的单一地球物理方法探测结果,本文研究采用的方法克服了单一地球物理场在勘探中的局限,有效提高了勘探结果的准确性,对非金属矿山地表河流渗漏水探测与安全开采矿山资源具有一定的现实指导意义。 展开更多
关键词 非金属矿山 渗漏水 探地雷达 流速仪 矿山安全
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基于组合带阻滤波器与样本熵的科氏流量计挂壁故障检测方法 被引量:1
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作者 思悦 张炎羿 +2 位作者 王丽洁 元振毅 李淑娟 《仪器仪表学报》 北大核心 2025年第2期132-140,共9页
测量管故障是影响和制约科氏流量计测量精度、可靠性和安全性的关键因素。挂壁故障是科氏流量计服役过程中极易出现的测量管故障形式之一,挂壁故障的产生使科氏流量计物理刚性值发生变化,导致计量校准因子发生偏移,直接影响质量流量及... 测量管故障是影响和制约科氏流量计测量精度、可靠性和安全性的关键因素。挂壁故障是科氏流量计服役过程中极易出现的测量管故障形式之一,挂壁故障的产生使科氏流量计物理刚性值发生变化,导致计量校准因子发生偏移,直接影响质量流量及其他流体信息的测量精度;另外,若挂壁故障不能及时被预警,则故障增长可能造成管道堵塞,严重时引发爆炸,造成重大工业安全事故。因此,检测科氏流量计服役状态、识别测量管挂壁故障,是提高科氏流量计测量精度、可靠性和安全性的迫切需求。故提出了一种基于组合带阻滤波器与样本熵的挂壁故障检测方法。由于振动响应信号通常包含多种模态特征信号和干扰信号。组合带阻滤波器能有效滤除干扰信号并保留目标模态特征信号。通过计算不同状态下模态特征信号的样本熵,可充分利用其对信号动态变化的高度敏感性。故障发生时,信号复杂性显著增加,样本熵值随之变化,为故障诊断和评估提供可靠依据。通过对比正常与故障状态的样本熵值,可定量分析故障严重程度,实现流量计故障状态的有效监测。实验结果表明,该方法可有效识别科氏流量计测量管的挂壁故障,且识别效果优于现有其他方法。 展开更多
关键词 科氏流量计 组合带阻滤波器 样本熵 故障检测
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延长油田井下分层注水流量计误差补偿方法 被引量:1
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作者 李硕 齐春民 +2 位作者 刘刚 李金阳 成城 《化工自动化及仪表》 2025年第1期32-38,共7页
提出一种针对延长油田井下分层注水的流量计误差补偿方法。根据流量计测量原理获取流量计测量值,并在此基础上完成流量计示值校正;针对由温度和流体状态引起的流量计误差,开展温度与流体状态的解耦处理。设计一种多元线性回归模型,分析... 提出一种针对延长油田井下分层注水的流量计误差补偿方法。根据流量计测量原理获取流量计测量值,并在此基础上完成流量计示值校正;针对由温度和流体状态引起的流量计误差,开展温度与流体状态的解耦处理。设计一种多元线性回归模型,分析多个温度因变量与测量值的关系,得到最优补偿系数估计值,将求取的系数向量代入根据多元线性回归模型得到的输出信号多元线性回归方程,即可得到温度补偿后的流量值。通过雷诺数获取注水流体状态,定义上临界速度和下临界速度,并设计补偿系数计算方法,完成误差补偿。实验结果表明:利用所提方法完成误差补偿后,提高了流量计的测量准确性。 展开更多
关键词 流量计 示值校正 误差补偿 多元线性回归模型 流体状态 井下分层注水
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基于ANSYS Workbench的农业灌溉计量阀整流器特性分析
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作者 张栋 李泷 《节水灌溉》 北大核心 2025年第10期114-119,共6页
农业灌溉计量阀性能直接影响农田管灌系统的计量精度与运行效率,普通农业灌溉计量阀内部常采用多圆孔水流通道结构的整流器进行整流。这种多孔整流器导致计量阀计量误差增加、能源消耗加剧。基于ANSYS Workbench软件构建水流域计算模型... 农业灌溉计量阀性能直接影响农田管灌系统的计量精度与运行效率,普通农业灌溉计量阀内部常采用多圆孔水流通道结构的整流器进行整流。这种多孔整流器导致计量阀计量误差增加、能源消耗加剧。基于ANSYS Workbench软件构建水流域计算模型,分析整流器内部的水流流速分布、压力梯度、湍流强度等参数,提出整流器结构改进方案,对比结构改进前后的水力性能,验证改进方案的有效性。结果表明,多孔整流器整流前后的水流流速差为1.93 m/s,水压差为2990 Pa,湍流强度峰值达到0.252 m^(2)/s^(2),整流前后的水压损耗受水流速度影响很大;改进后的整流器增加了二次曲面导流结构,水流通道改进为栅格结构,使水流流速差降至0.793 m/s,水流压差降至742 Pa,最大湍流强度降至0.145 m^(2)/s^(2),水压损耗受水流速度影响显著减少。综上,改进后的整流器有效抑制了湍流现象,使各区域水流速度分布更均匀,同时降低了整流前后的水压损耗,适用于农业灌溉计量阀内部结构优化设计。 展开更多
关键词 ANSYS Workbench 计量阀整流器 水力性能 流速分布 压力梯度 湍流强度
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蝶阀对超声波流量计测量误差的影响及修正模型
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作者 王晓东 李丹丹 +4 位作者 张晓菡 岳宇 李云飞 武晓菲 邢兰昌 《科学技术与工程》 北大核心 2025年第28期12023-12032,共10页
超声波流量计(ultrasonic flow meters,UFMs)的测量性能对安装位置极为敏感,实际应用中不可避免地遇到非标准测试条件。针对常见的阀门扰流件,目前尚缺乏相应的误差影响规律及误差修正模型研究。以蝶阀为阀门研究对象,构建不同入口流速... 超声波流量计(ultrasonic flow meters,UFMs)的测量性能对安装位置极为敏感,实际应用中不可避免地遇到非标准测试条件。针对常见的阀门扰流件,目前尚缺乏相应的误差影响规律及误差修正模型研究。以蝶阀为阀门研究对象,构建不同入口流速、管径、阀门位置和开度等条件下超声波流量测量过程的有限元数值模型,探讨蝶阀对流场和误差特性的影响规律,最终建立超声波流量计的测量误差修正模型。结果表明:管道内流体受到阀板阻挡而引起过流截面积缩小,阀板与管壁之间形成高流速区域;阀门上游和下游管道截面上的流速分布发生畸变,畸变程度随着距离的增大而逐渐减弱;对于管径的影响,当流量计距下游阀门大于0.6D时(D为管道直径),根据误差特性可以把管径分为两组,分别为0.1~0.3 m和0.4~0.6 m,可针对两组管径范围分别建立误差修正模型;当流量计距离上游阀门大于5D,管径0.1~0.6 m范围内的测量误差一致性较强,可建立统一的误差修正模型;经模型修正后,流量测量误差低于2.0%;对于阀门开度的影响,当阀门开度在30°~75°范围内,流量计距离下游和上游阀门分别大于0.6D和5D时,测量误差一致性较强,在阀门位置确定的条件下,针对不同阀门开度可以建立统一的修正模型;经模型修正后,流量测量误差低于2.0%。研究成果为拓展超声波流量计在非标测试条件下的应用范围提供了理论依据和模型支撑。 展开更多
关键词 超声波流量计(UFM) 蝶阀 流场特征 误差特性 误差修正 数值模拟
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