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Reliability and Validity of Hand-Held Dynamometer and Hand-Held Sphygmomanometer for Testing Shoulder Isometric External and Internal Rotator Muscles Strength
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作者 Francesco Bettariga Nicola Francesco Lopomo +3 位作者 Fabio Civera Stefano Giuseppe Lazzarini Lisa Mantovani Luca Maestroni 《Journal of Science in Sport and Exercise》 CSCD 2024年第4期386-393,共8页
Background Shoulder strength evaluation is a recommended procedure in musculoskeletal rehabilitation.Aim To examine hand-held sphygmomanometer(HHS)and hand-held dynamometer(HHD)intra-and inter-rater reliability during... Background Shoulder strength evaluation is a recommended procedure in musculoskeletal rehabilitation.Aim To examine hand-held sphygmomanometer(HHS)and hand-held dynamometer(HHD)intra-and inter-rater reliability during isometric shoulder external and internal rotation strength testing in prone rotation position in asymptomatic participants,and to compare these two testing modalities.Design Reliability study.Methods A total of 20 asymptomatic participants(27.7±7.4 years;77.1±10.1 kg)attended a strength assessment consisting of HHS and HHD tests.Reliability was assessed using the intra-class correlation coefficient(ICC)with 95%confidence intervals(CI),coefficient of variation(CV)with 95%CI,and standard error of measurement(SEM).Pearson correlation and linear regression analysis were used to compare HHS and HHD testing modalities.Results“Good”to“excellent”intra(ICC range=0.896 to 0.979)and inter-rater reliability scores(ICC range=0.850 to 0.978)were displayed during both HHS and HHD tests during internal and external rotation strength assessments.Linear relationships between HHS and HHD measures were found,with coefficients of determination(R2)ranging between 0.60 and 0.79.Conclusion HHS and HHD resulted to be reliable strength assessment modalities for clinical practice.These assessment modes can be equally valid in assessing intra and inter-limb asymmetries in isometric shoulder rotation strength.The affordability and availability of HHS in ordinary clinical settings can facilitate its implementation in musculoskeletal practice. 展开更多
关键词 SPHYGMOMANOMETER hand-held dynamometer Reliability SHOULDER
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Reliability of the K-Force Muscle Controller Dynamometer on Eccentric and Isometric Hip Adduction Strength
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作者 Christos Pippas Antonis Emmanouilidis +2 位作者 Stefanos Karanasios George Koumantakis George Gioftsos 《Open Journal of Therapy and Rehabilitation》 2024年第3期224-235,共12页
Hip adduction strength tests are commonly used in clinical practice to provide an accurate diagnosis of groin injuries. Athletes with reduced adductor muscle strength are at risk of developing groin injuries. Our stud... Hip adduction strength tests are commonly used in clinical practice to provide an accurate diagnosis of groin injuries. Athletes with reduced adductor muscle strength are at risk of developing groin injuries. Our study aimed to evaluate the relative and absolute test-retest reliability of the side-lying eccentric hip adduction strength test and the long-lever adduction squeeze test using the K-Force hand-held dynamometer. Twenty physically active male individuals with a mean age (±SD) of 30.7 (±7.3) years were included. Both tests presented excellent test-retest reliability (Intraclass Correlation Coefficient: 0.77 - 0.95). The best and mean scores of the eccentric and isometric tests presented the smallest test-retest variation (MDC%: 12.8 - 14.9 and MDC%: 14.6 - 18.7, respectively). Our study showed that the K-Force dynamometer has excellent reliability for assessing hip adduction strength in two different testing positions. We suggest the best and mean of three repetitions for clinical practice as they present the lowest variability. Further research evaluating its clinimetric properties in different populations and gender is recommended. 展开更多
关键词 ADDUCTOR GROIN Strength Testing dynamometer RELIABILITY
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Robot driver for vehicle durability emission test on chassis dynamometer 被引量:9
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作者 陈晓冰 张为公 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期33-38,共6页
A method for a vehicle durability emission test using a robot driver insteadof human drivers on the chassis dynamometer is presented. The system architecture of vehicledurability emission test cell, the road load simu... A method for a vehicle durability emission test using a robot driver insteadof human drivers on the chassis dynamometer is presented. The system architecture of vehicledurability emission test cell, the road load simulation strategy and the tele-monitoring systembased on Browser/Client structure are described. Furthermore, the construction of the robot driver,vehicle performance self-learning algorithm, multi-mode vehicle control model and vehicle speedtracking strategy based on fuzzy logic arealso discussed. Besides, the capability of controlparameters self-compensation on-line makes it possible to compensate the wear of vehicle componentsand the variety of clutch true bite point during the long term test. Experimental results show thattherobot driver can be applicable to a wide variety of vehicles and the obtained results stay withina tolerance band of ± 2 km/h. Moreover the robot driver is able to control tested vehicles withgood repeatability and consistency; therefore, this methodpresents a solution to eliminate theuncertainty of emission test results by human drivers and to ensure the accuracy and reliability ofemission test results. 展开更多
关键词 robot driver durability emission test chassis dynamometer driving testcycle
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Design and simulation of electrical dynamometer using improved DTC induction motor driver 被引量:1
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作者 ZHU Cheng-li WANG Yan-zhong HOU Liang-wei 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1360-1368,共9页
AC motors, especially the squirrel cage induction motors have the advantages of simple structure, good reliability and low cost. They are more suitable to be used as electrical dynamometers to provide dynamic load for... AC motors, especially the squirrel cage induction motors have the advantages of simple structure, good reliability and low cost. They are more suitable to be used as electrical dynamometers to provide dynamic load for bench test systems. But, the speed and torque of induction motors are not easy to be controlled accurately. In this work, an electrical dynamometer based on the induction motor is proposed. In order to get better control performance of torque and speed of induction motor, an improved direct torque control method(DTC) is also developed based on the space vector modulation(SVM) technique. The performance of the proposed dynamometer system is validated in the Matlab/Simulink platform. The simulation results show that the new dynamometer has good torque and stator flux response. And the torque and stator current ripples of it are reduced significantly compared with using the conventional DTC method. 展开更多
关键词 dynamometer induction motor DIRECT TORQUE CONTROL (DTC) DIRECT TORQUE CONTROL method-space vector modulation DTC-SVM PI controller
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Soft measurement model on torque of alternating current electrical dynamometer including copper loss and iron loss 被引量:1
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作者 ZHONG Ding-qing WANG Ai-lun HE Qian 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第8期2272-2280,共9页
Alternating current electrical dynamometer is a common device to measure the torque of engines, such as the gasoline engine. In order to solve the problems such as high cost, high energy consumption and complicated me... Alternating current electrical dynamometer is a common device to measure the torque of engines, such as the gasoline engine. In order to solve the problems such as high cost, high energy consumption and complicated measurement system which exists in the direct measurement on the torque of alternating current electrical dynamometer, copper loss and iron loss are taken as two key factors and a soft-sensing model on the torque of alternating current electrical dynamometer is established using the fuzzy least square support vector machine (FLS-SVM). Then, the FLS-SVM parameters such as penalty factor and kernel parameter are optimized by adaptive genetic algorithm, torque soft-sensing is investigated in the alternating current electrical dynamometer, as well as the energy feedback efficiency and energy consumption during the measurement phase of a gasoline engine loading continual test is obtained. The results show that the minimum soft-sensing error of torque is about 0.0018, and it fluctuates within a range from -0.3 to 0.3 N·m. FLS-SVM soft-sensing method can increase by 1.6% power generation feedback compared with direct measurement, and it can save 500 kJ fuel consumption in the gasoline engine loading continual test. Therefore, the estimation accuracy of the soft measurement model on the torque of alternating current electrical dynamometer including copper loss and iron loss is high and this indirect measurement method can be feasible to reduce production cost of the alternating current electrical dynamometer and energy consumption during the torque measurement phase of a gasoline engine, replacing the direct method of torque measurement. 展开更多
关键词 TORQUE fuzzy theory least square support vector machine alternating current electrical dynamometer
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Test-retest strength reliability of the Electronic Push/Pull Dynamometer (EPPD) in the measurement of the quadriceps and hamstring muscles on a new chair
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作者 Mikhled F. Maayah Mohammad D. Al-Jarrah +7 位作者 Saad S. El Zahrani Ali H. Alzahrani Emad T. Ahmedv Amr A. Abdel-Aziem Gopichandran Lakshmanan Nabeel A. Almawajdeh Muhsen B. Alsufiany Yaser O. M. Abu Asi 《Open Journal of Internal Medicine》 2012年第2期123-128,共6页
Background: Test-retest strength reliability of the Electronic Push/Pull Dynamometer (EPPD) in the measurement of the extensor and flexor muscles on a new constructed chair. The objective of the study was to assess re... Background: Test-retest strength reliability of the Electronic Push/Pull Dynamometer (EPPD) in the measurement of the extensor and flexor muscles on a new constructed chair. The objective of the study was to assess reliability of Electronic Push/Pull Dynamometer in the measurement of the knee flexion and extension at 90° and 60° on a new constructed chair. The aims of the author: To assess reliability of Electronic Push/Pull Dynamometer in the measurement of the knee flexion and extension at 90° and 60° on a new constructed chair. Design: A test-retest reliability study. Subjects: One hundred healthy students male and female (mean age, 21y). Methods: Maximum isometric strength of the quadriceps and hamstring muscle groups was measured using the EPPD were recorded at 60° and 90° for 3 trials on 2 occasions. Reliability was assessed with the Intraclass correlation coefficient (ICC), mean and standard deviation (SD) of measurements, and smallest real differences were calculated for the maximum and for the mean and work of the 3 repetitions. Results: Mean strength ranged from 50.44 kg for knee flexion to 55.76 kg for knee extension 50.44 kg to 61.98 kg at 90° hip flexion. Test-retest reliability Intraclass correlation coefficients (ICCs) ranged from 0.85 to 0.99. ICCs for test-retest reliability ranged from 0.780 to 0.998. Conclusions: The results of the reliability study indicate that the EPPD in reliable dynamometer to use in determining lower limb muscle force production. It can be used to measure disease progression and to evaluate changes in knee extension and flexion strength at the individual patient level. 展开更多
关键词 Muscle Strength Reliability TEST-RETEST hand-held dynamometer ELECTRONIC Pull/Push dynamometer
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Model Predictive Control Coupled with Artificial Intelligence for Eddy Current Dynamometers
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作者 İhsan Uluocak Hakan Yavuz 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期221-234,共14页
The recent studies on Artificial Intelligence(AI)accompanied by enhanced computing capabilities supports increasing attention into traditional control methods coupled with AI learning methods in an attempt to bringing... The recent studies on Artificial Intelligence(AI)accompanied by enhanced computing capabilities supports increasing attention into traditional control methods coupled with AI learning methods in an attempt to bringing adap-tiveness and fast responding features.The Model Predictive Control(MPC)tech-nique is a widely used,safe and reliable control method based on constraints.On the other hand,the Eddy Current dynamometers are highly nonlinear braking sys-tems whose performance parameters are related to many processes related vari-ables.This study is based on an adaptive model predictive control that utilizes selected AI methods.The presented approach presents an updated the mathema-tical model of an Eddy Current Dynamometer based on experimentally obtained system operational data.Finally,the comparison of AI methods and related learn-ing performances based on the assessment technique of mean absolute percentage error(MAPE)issues are discussed.The results indicate that Single Hidden Layer Neural Network(SHLNN),General Regression Neural Network(GRNN),Radial Basis Network(RBNN),Neuro Fuzzy Network(ANFIS)coupled MPC have quite satisfying performances.The presented results indicate that,amongst them,GRNN appears to provide the best performance. 展开更多
关键词 Model predictive control eddy current dynamometer artificial intelligence GRNN RBNN ANFIS
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Design and Manufacture of a Mobile Dynamometer
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作者 Animashaun Idriss Woods Gerry 《Journal of Mechanics Engineering and Automation》 2018年第6期273-279,共7页
DIT has competed for a number of years in the Formula Student competition with petrol engine propelled vehicles.Dynamometer testing on these engines was traditionally outsourced.In2017/2018a decision was made to comme... DIT has competed for a number of years in the Formula Student competition with petrol engine propelled vehicles.Dynamometer testing on these engines was traditionally outsourced.In2017/2018a decision was made to commence the design of an electric vehicle.Access to a suitable dynamometer for regular testing became more important than ever in order to fully characterise the electric motors the gearbox combinations and optimise the performance of the formula student electric vehicle.This paper deals with the design and manufacture and component selection for a mobile dynamometer that can accurately simulate racetrack conditions and apply typical loading cycles to a motor producing torque,power and speed values from a typical drivetrain.The dynamometer described uses a particle brake to apply the loads,a datum M425torque transducer to measure torque and a National Instruments LabVIEW interface to display and store data during testing.Safety is of vital importance and this paper describes the high-safety standards applied during the design and manufacture phase.With the implementation of an electronic control circuit,motor characteristics charts are produced,analysed and utilised for calibration and benchmarking for future motor test runs.Aim:Design&Manufacture of a mobile dynamometer unit to produce torque,speed and power values from the drive train of a motor. 展开更多
关键词 FORMULA SAE engine testing dynamometer data acquisition TORQUE TRANSDUCER
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基于半监督学习的抽油机井故障诊断方法研究
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作者 何岩峰 王相 +2 位作者 褚宪翔 邵志伟 李明 《钻采工艺》 北大核心 2025年第1期228-237,共10页
近年来,基于深度学习的油井故障诊断方法取得了显著进展,但这类方法的性能高度依赖标注样本集的数量和质量,且深度学习模型经过训练后可诊断的故障类型被固定,增加新类型需要重新收集样本并进行再训练,灵活性不足。为解决上述问题,文章... 近年来,基于深度学习的油井故障诊断方法取得了显著进展,但这类方法的性能高度依赖标注样本集的数量和质量,且深度学习模型经过训练后可诊断的故障类型被固定,增加新类型需要重新收集样本并进行再训练,灵活性不足。为解决上述问题,文章提出了一种基于半监督学习的抽油机井故障诊断方法。该方法利用VGG19与小批量K均值相结合对大量示功图进行自动聚类分析,通过对聚类结果实施批量标注,能够有效提升样本分类的科学性及标注效率。在此基础上,构建基于欧氏距离的K近邻算法实现故障诊断,避免了深度学习方法中繁琐的模型训练及参数调优过程,同时支持样本集动态更新。基于矿场实际数据的实验结果显示,所提出的半监督学习诊断方法可达到与深度学习方法相当的准确率(均超过90%),但在前期准备阶段所需的时间成本减少了90%以上。更重要的是,当面对新出现的故障类型时,本方法能够快速响应并适应,极大地增强了抽油机井故障诊断系统的灵活性。 展开更多
关键词 抽油机井 故障诊断 示功图 机器学习 半监督学习
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面向多源数据的CNN-XGB抽油机井故障诊断技术
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作者 张黎明 吴雨垣 +4 位作者 李敏 尹承哲 王鑫炎 刘冰 王树源 《石油钻采工艺》 北大核心 2025年第1期44-52,共9页
在油田生产过程中,抽油机井的稳定运行对于提高生产效率和经济效益至关重要。然而,现有的故障诊断技术大多依赖于单一数据源(如示功图数据或生产参数)进行模型训练,在面对杆断脱和泵漏失等复杂工况时,诊断精度严重不足,甚至出现诊断失... 在油田生产过程中,抽油机井的稳定运行对于提高生产效率和经济效益至关重要。然而,现有的故障诊断技术大多依赖于单一数据源(如示功图数据或生产参数)进行模型训练,在面对杆断脱和泵漏失等复杂工况时,诊断精度严重不足,甚至出现诊断失效的情况。为此,提出了一种面向多源数据融合的CNN-XGB故障诊断模型,结合卷积神经网络(CNN)和极端梯度提升(XGB)算法,分别提取泵功图图像特征和油井生产参数特征,从多个角度捕捉反映不同工况的特征信息。通过将这些特征整合并输入多层感知机(MLP),模型能够实现更精准的分类结果,从而显著提高特异性识别能力。实验结果表明,该融合模型在6种典型工况下的诊断精确率和召回率均超过95%,相较于传统的CNN和XGB模型,展现出更高的诊断准确性和鲁棒性。这一方法有效解决了单一数据源在故障诊断中的局限性,为油田抽油机井工况的智能诊断提供了一种新的技术手段,具有重要的实际应用价值。 展开更多
关键词 抽油机井 示功图 多源数据 卷积神经网络 极端梯度提升 模型融合 工况诊断
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基于有效冲程新算法的功图软件设计及应用
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作者 温后珍 陈颖 +3 位作者 吕岩 孟碧霞 张义举 李媛媛 《化工自动化及仪表》 2025年第4期580-586,共7页
油井产液量的准确计量可为油井采油工艺参数调节提供依据。传统功图量油算法大多通过计算泵功图有效冲程的方式计算产液量,但在生产实际中传统算法得到的产液量与实际产液量误差较大。因此,提出一种利用泵功图的包络矩形4个极点确定泵功... 油井产液量的准确计量可为油井采油工艺参数调节提供依据。传统功图量油算法大多通过计算泵功图有效冲程的方式计算产液量,但在生产实际中传统算法得到的产液量与实际产液量误差较大。因此,提出一种利用泵功图的包络矩形4个极点确定泵功图ABCD点进而求得泵有效冲程的新方法,并据此开发示功图量油软件系统。现场验证结果表明:油井产液量相对误差大多在10%以内,最小达到0.1%。对500口井预测产液量与实测产液量进行误差对比发现,准确率高达94.1%。 展开更多
关键词 示功图量油 数字化油田 柱塞有效冲程 功图计产 极点法
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基于抽油机工况的特征提取与建立和全域故障识别 被引量:1
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作者 任泰珠 樊军 蒋夏新 《机械强度》 北大核心 2025年第1期12-19,共8页
针对目前抽油机井下工况故障特征分类任务难以解决,使得所建立诊断模型适应性差且识别率低的问题,通过对抽油机阀门和抽油杆运动状态的分析,首先将示功图进行数学形态学预处理;然后提出阀门开闭点获取和载荷变化特征获取的两种方法,提... 针对目前抽油机井下工况故障特征分类任务难以解决,使得所建立诊断模型适应性差且识别率低的问题,通过对抽油机阀门和抽油杆运动状态的分析,首先将示功图进行数学形态学预处理;然后提出阀门开闭点获取和载荷变化特征获取的两种方法,提取到抽油机全域故障的54个全新特征,建立了抽油机工况的特征库;最后运用决策树、Logistic回归和支持向量机算法,验证了在不同工况下,该特征库均具有较好的分类效果,评估了不同故障的工况特征指标,得到各工况私有规则库。研究结果表明,提取的特征能够有效识别出抽油机全域故障,并且具有较高的识别精度。 展开更多
关键词 抽油机 示功图 特征提取 故障识别 阀门
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基于底盘测功机测试的汽车道路噪声模拟与适用性研究
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作者 康强 李欢 +1 位作者 左曙光 吴旭东 《中国工程机械学报》 北大核心 2025年第4期575-579,共5页
为将底盘测功机测试的道路噪声信号模拟为实际道路噪声,首先采用能量叠加法确定主要能量占比频段为目标频带,在目标频带内利用速度平均法对车内不同位置及不同车速下的测功机测试的道路噪声进行修正,消除由转鼓引起的尖锐谐波的影响;随... 为将底盘测功机测试的道路噪声信号模拟为实际道路噪声,首先采用能量叠加法确定主要能量占比频段为目标频带,在目标频带内利用速度平均法对车内不同位置及不同车速下的测功机测试的道路噪声进行修正,消除由转鼓引起的尖锐谐波的影响;随后对测功机鼓面与实际路面所产生的噪声之间进行权重系数的计算,将测功机所测的噪声信号模拟为实际道路噪声。结果表明:该模拟方法对不同车速下的实际道路噪声适用性强,模拟误差均在2 dB以内;对于结构相似的不同车型,也能实现良好的模拟效果;但是对于结构相差较大的车型,无法使用同一模拟权重系数进行计算,需要分车型单独计算才能实现模拟效果。 展开更多
关键词 底盘测功机 能量叠加法 速度平均法 道路噪声模拟 适用性
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考虑柴油机测功系统接入的配电网韧性提升方法研究
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作者 窦真兰 张春雁 +2 位作者 张继行 王玲玲 蒋传文 《高压电器》 北大核心 2025年第5期302-310,共9页
柴油机试车是测定柴油机性能指标并进行验收的重要步骤,主要的测试平台为电力测功系统,其试车过程中产生的机械能通过电力测功平台转化为电能,再通过负载箱转化为热能,这一过程造成了巨大的能源浪费。目前极端灾害造成的小概率、大影响... 柴油机试车是测定柴油机性能指标并进行验收的重要步骤,主要的测试平台为电力测功系统,其试车过程中产生的机械能通过电力测功平台转化为电能,再通过负载箱转化为热能,这一过程造成了巨大的能源浪费。目前极端灾害造成的小概率、大影响事件严重影响了配电网的运行安全,而灵活性分布式资源的接入是提升配电网韧性、抵御极端灾害的有效措施。因此文中考虑将测功平台的电能回馈到配电网作为灵活性资源进行支撑,并针对柴油机测功系统的接入对配电网韧性影响进行研究,以寻找灾害场景下测功系统最优调度策略。首先,对柴油机测功系统出力特性进行建模;其次,选取韧性关键指标,量化测功系统并网对配电网韧性的影响程度,并以韧性提高为目标,建立柴油机测功系统最优调度模型,该问题包含多个决策主体,采用多代理强化学习方法进行求解;最后进行算例分析,仿真模拟测功系统作为分布式能源,在不同容量、并网节点的情况下接入对于配电网韧性的影响,并求解其最优调度策略。算例分析表明,柴油机测功系统的接入有助于提升配电网韧性,降低了灾害场景下的配电网负荷损失率。 展开更多
关键词 柴油机测功系统 配电网 韧性提升 分布式资源
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基于国标和美标的滑行阻力底盘测功机模拟方法对比研究 被引量:1
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作者 王梦凡 严康 +2 位作者 闵浪 赵九州 李奇 《专用汽车》 2025年第5期8-15,共8页
根据GB 18352.6—2016和SAE J2264—2023,总结了完整的国标和美标滑行阻力底盘测功机模拟流程。使用某纯电车开展滑行阻力模拟试验,对比了两种标准的模拟结果,结果表明,模拟阻力与目标阻力的差值均满足标准中最大误差±10 N的要求... 根据GB 18352.6—2016和SAE J2264—2023,总结了完整的国标和美标滑行阻力底盘测功机模拟流程。使用某纯电车开展滑行阻力模拟试验,对比了两种标准的模拟结果,结果表明,模拟阻力与目标阻力的差值均满足标准中最大误差±10 N的要求。计算了CLTC-P和UDDS曲线的理论循环需求能量,开展了对应试验并测量循环需求能量,结果表明两种模拟方法在进行循环试验时基本一致,可以采用国标方法等效替代美标滑行。研究结论对下一阶段排放和能耗标准发展、国内汽车海外出口认证和相关科学研究具有参考意义。 展开更多
关键词 SAE J2264 滑行阻力 底盘测功机
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燃气轮机高速水力测功器转子系统振动分析
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作者 张虞 廖鹏 +3 位作者 肖焱毅 陈波 陈书恒 王军 《热能动力工程》 北大核心 2025年第7期65-71,共7页
为了解决燃气轮机测试用水力测功器主轴和转子所组成的结构系统在运行过程中受水流作用造成的固有频率显著降低的问题,采用Donald/Burrill旋转体结构附连水质量研究方法,基于动力学基本方程开展了高速水力测功器转子系统振动特性研究。... 为了解决燃气轮机测试用水力测功器主轴和转子所组成的结构系统在运行过程中受水流作用造成的固有频率显著降低的问题,采用Donald/Burrill旋转体结构附连水质量研究方法,基于动力学基本方程开展了高速水力测功器转子系统振动特性研究。首先,采用Donald/Burrill旋转体结构附连水计算方法,结合Solidworks三维建模平台,开展了水力测功器有水状态下转子系统的附连水质量计算分析;然后,基于ANSYS Workbench仿真计算平台,在水力测功器无水和有水状态下开展了系统前5阶固有频率分析;最后,在100~1000 Hz范围内开展频率响应分析和某随机载荷谱下的随机振动分析,对比分析了主轴和转子系统在无水和满水状态下的振动响应。结果表明:湿模态比干模态的固有频率下降超过6%;湿模态下的主轴和转子系统的频率响应和随机振动响应峰值前移,表明湿模态下的主轴和转子系统更易发生共振;随机振动的应力响应显示,共振时的应力峰值超过初始应力100倍,对系统具有较强的破坏性。 展开更多
关键词 水力测功器 附连水质量 固有频率 湿模态分析 有限元
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某水力测功器快速调心优化设计
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作者 吴支繁 付金辉 +1 位作者 罗昕 陆思玮 《内燃机与配件》 2025年第10期90-92,共3页
本文针对某高速水力测功器位置度调整裕度不足的问题开展针对性优化设计,通过新设计的调心底板,增大了高速水力测功器位置度调整裕度。同时本文新设计了调心工装,并借助快插接头,提高了水力测功器调心过程中的工作效率。
关键词 水力测功器 调心 优化
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基于转毂试验的电驱阶次噪声分离方法
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作者 武斌 毕金亮 +2 位作者 汤乐超 杨晓涛 何思彤 《农业装备与车辆工程》 2025年第1期125-128,共4页
传统的实车道路测试难以全面覆盖电驱系统在不同扭矩区间和不同转速区间的运行工况,针对上述问题,提出一种基于转毂试验的新能源汽车电驱阶次噪声分离方法。以某电动汽车的匀加速工况为例,将某主要阶次下的车带毂噪声与毂带车噪声能量做... 传统的实车道路测试难以全面覆盖电驱系统在不同扭矩区间和不同转速区间的运行工况,针对上述问题,提出一种基于转毂试验的新能源汽车电驱阶次噪声分离方法。以某电动汽车的匀加速工况为例,将某主要阶次下的车带毂噪声与毂带车噪声能量做差,最后求得电驱的阶次噪声能量并形成不同油门开度下的电驱阶次噪声map图。由map图可知,随着转速的增加,电驱扭矩在逐渐减小,但其阶次噪声在逐渐增加。相较于传统的道路测试,所提方法进一步完善了电驱阶次噪声评价体系,不仅可以全面覆盖电驱的运行工况,还能够依据能量叠加理论将电驱阶次噪声进行分离,以确定在电驱单独激励下的整车电驱阶次噪声水平,为新能源汽车电驱NVH性能对标与控制提供了新思路。 展开更多
关键词 转毂试验 电驱系统 噪声分离
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基于MCT组合工况的电动车续驶里程测试方法
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作者 郭成胜 杜闯 +2 位作者 姜智杰 雷利刚 孙龙 《小型内燃机与车辆技术》 2025年第3期50-56,共7页
美国标准SAE J1634-2017《电动汽车能耗和续航里程测试程序》规定续航超过97 km的电动车续驶里程测试采用MCT组合工况,MCT组合工况由4个UDDS试验循环及2个HFEDS试验循环和等速放电工况组成,工况运行结束后计算UDDS及HFEDS循环权重分配系... 美国标准SAE J1634-2017《电动汽车能耗和续航里程测试程序》规定续航超过97 km的电动车续驶里程测试采用MCT组合工况,MCT组合工况由4个UDDS试验循环及2个HFEDS试验循环和等速放电工况组成,工况运行结束后计算UDDS及HFEDS循环权重分配系数,通过加权能耗分别计算车辆UDDS及HFEDS试验循环续航。基于底盘测功机、环境舱及功率分析仪系统对美标基于权重系数的续驶里程计算方法进行研究,并对组合工况电能特征进行分析,从而形成完整的美标电动车续驶里程测试流程。 展开更多
关键词 电动汽车 UDDS HFEDS MCT 权重系数 底盘测功机
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柴油车道路试验验证及DPF累碳对排放的影响
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作者 杨国良 武鑫 +1 位作者 邓蛟 钱超 《小型内燃机与车辆技术》 2025年第4期49-52,58,共5页
研究一辆满足国六排放标准的柴油车在相同运转方式下,实际道路和转毂台架排放试验结果的一致性,以及DPF颗粒积载状态对排放测试结果的影响。结果表明:无论在道路上还是在转毂台架上试验,只要运转的方式接近其排放结果也接近,但排放结果... 研究一辆满足国六排放标准的柴油车在相同运转方式下,实际道路和转毂台架排放试验结果的一致性,以及DPF颗粒积载状态对排放测试结果的影响。结果表明:无论在道路上还是在转毂台架上试验,只要运转的方式接近其排放结果也接近,但排放结果受转毂加载及驾驶行为影响;在较低排放的工况下,SCR净化效率显著影响NO_(x)尾排结果;DPF适当累碳后在WLTC循环高速阶段易发生被动再生,从而增大PN和NO_(x)排放,但在非再生期间,PN排放有降低的倾向;PEMS对低浓度排放区域测试精度较差,其中CO最为明显;PEMS和CVS计算的碳质量流量相关系数R^(2)可达到0.92。 展开更多
关键词 实际道路排放 转毂台架 DPF 柴油车 PEMS
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