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Bench Test Modeling for Current and Future PCMO Fuel Economy Requirements
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作者 Mark T. Devlin Cheng C. Kuo +1 位作者 John M. Pietras Zhang Yun 《润滑油》 CAS 2008年第1期55-61,共7页
The automotive and lubricant industries have been placing increased emphasis on the fuel economy benefits of today′s modern passenger car motor oils.The current ILSAC GF-4 specification has more stringent requirement... The automotive and lubricant industries have been placing increased emphasis on the fuel economy benefits of today′s modern passenger car motor oils.The current ILSAC GF-4 specification has more stringent requirements than previous ILSAC specifications,and the proposed future ILSAC GF-5 specification is looking at further improvements in the lubricant′s fuel economy performance.To address these needs,Afton Chemical has developed correlations between the rheological and frictional properties of oils and fuel economy measured in engine and field tests.In this paper we will present correlations between lubricants′ physical properties and fuel economy measured in vehicles and engine tests.These tools have been used to develop current commercial oils which are being used extensively to meet today′s OEM needs. 展开更多
关键词 燃料经济性 台架试验模型 流变学 摩擦力 汽车 机油
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In vitro bench testing using patient-specific 3D models for percutaneous pulmonary valve implantation with Venus P-valve 被引量:1
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作者 Yu Han Zehua Shao +7 位作者 Zirui Sun Yan Han Hongdang Xu Shubo Song Xiangbin Pan Peter P.T.de Jaegere Taibing Fan Gejun Zhang 《Chinese Medical Journal》 SCIE CAS CSCD 2024年第8期990-996,共7页
Background:Due to the wide variety of morphology,size,and dynamics,selecting an optimal valve size and location poses great difficulty in percutaneous pulmonary valve implantation(PPVI).This study aimed to report our ... Background:Due to the wide variety of morphology,size,and dynamics,selecting an optimal valve size and location poses great difficulty in percutaneous pulmonary valve implantation(PPVI).This study aimed to report our experience with in vitro bench testing using patient-specific three-dimensional(3D)-printed models for planning PPVI with the Venus P-valve.Methods:Patient-specific 3D soft models were generated using PolyJet printing with a compliant synthetic material in 15 patients scheduled to undergo PPVI between July 2018 and July 2020 in Central China Fuwai Hospital of Zhengzhou University.Results:3D model bench testing altered treatment strategy in all patients(100%).One patient was referred for surgery because testing revealed that even the largest Venus P-valve would not anchor properly.In the remaining 14 patients,valve size and/or implantation location was altered to avoid valve migration and/or compression coronary artery.In four patients,it was decided to change the point anchoring because of inverted cone-shaped right ventricular outflow tract(RVOT)(n=2)or risk of compression coronary artery(n=2).Concerning sizing,we found that an oversize of 2-5 mm suffices.Anchoring of the valve was dictated by the flaring of the in-and outflow portion in the pulmonary artery.PPVI was successful in all 14 patients(absence of valve migration,no coronary compression,and none-to-mild residual pulmonary regurgitation[PR]).The diameter of the Venus P-valve in the 3D simulation group was significantly smaller than that of the conventional planning group(36[2]vs.32[4],Z=-3.77,P<0.001).Conclusions:In vitro testing indicated no need to oversize the Venus P-valve to the degree recommended by the balloon-sizing technique,as 2-5 mm sufficed. 展开更多
关键词 Heart valve prosthesis implantation Percutaneous pulmonary valve intervention Pulmonary regurgitation bench testing 3D printing Venus P-valve
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Inertia Matching During Dynamic Simulation of Vehicle Drive System on Test Bench 被引量:4
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作者 宋强 孙逢春 +1 位作者 郑慕侨 顾进超 《Journal of Beijing Institute of Technology》 EI CAS 2004年第2期197-201,共5页
Framework and basic parameters of a test bench for motor drive system of electric vehicle (EV) are illuminated. Two kinds of electric drive models, one was for the electric vehicle drived on real road, the other was f... Framework and basic parameters of a test bench for motor drive system of electric vehicle (EV) are illuminated. Two kinds of electric drive models, one was for the electric vehicle drived on real road, the other was for that on test bench, are put forward. Then, dynamic analysis of these models is made in detail. Inertia matching method of the test bench is researched and some useful formulas and graphs are brought forward. The experiment of an electric bus is introduced in order to explain the usage of this inertia matching method. 展开更多
关键词 electric drive test bench FRAMEWORK dynamic analysis inertia matching
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Electronic Unit Pump Test Bench Development and Pump Properties Research 被引量:1
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作者 刘波澜 黄英 +1 位作者 张付军 赵长禄 《Journal of Beijing Institute of Technology》 EI CAS 2006年第4期384-388,共5页
A unit pump test bench is developed on an in-line pump test platform. The bench is composed of pump adapting assembly, fuel supply subsystem, lubricating subsystem and a control unit. A crank angle domain injection co... A unit pump test bench is developed on an in-line pump test platform. The bench is composed of pump adapting assembly, fuel supply subsystem, lubricating subsystem and a control unit. A crank angle domain injection control method is given out and the control accuracy can be 0.1° crank degree. The bench can test both mechanical unit pump and electronic unit pump. A test model-PLD12 electronic unit pump is tested. Full pump delivery map and some influence factors test is done. Experimental results show that the injection quantity is linear with the delivery angle. The quantity change rate is 15% when fuel temperature increases 30 ℃. The delivery quantity per cycle increases 30 mg at 28 V drive voltage. The average delivery difference for two same type pumps is 5 %. Test results show that the bench can be used for unit pump verification. 展开更多
关键词 unit pump test bench control system experimental research
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Changes in coronary bifurcations after stent placement in the main vessel and balloon opening of stent cells:theory and practical verification on a bench-test model 被引量:1
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作者 Dobrin Vassilev Robert Gil 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2008年第1期43-49,共7页
Objective To describe changes that occur in stent morphology and structure after its implantation in coronary bifurcation.Side branch (SB) compromise after stenting of main vessel in coronary bifurcation is a major in... Objective To describe changes that occur in stent morphology and structure after its implantation in coronary bifurcation.Side branch (SB) compromise after stenting of main vessel in coronary bifurcation is a major intraprocedural problem and for the long term,as a place of restenosis.Methods We created an elastic wall model (parent vessel diameter 3.5mm,daughter branches 3.5mm and 2.75mm)with 30,45 and 60 degree distal angulation between branches.After stent implantation,struts to the side branch were opened with 2.0mm and consequently 3.0mm diameter balloons.Subsequent balloon redilatations and kissing balloon inflations (KBI) were performed.All stages of the procedure were photographed with magnification up to 100 times.Results We found that the leading mechanism for side branch compromise was carina displacement,and discovered theoretical description for expected ostial stenosis severity.Based on our model we found that displacement of bifurcation flow divider cause SB stenosis with almost perfect coincidence with our theoretical predictions.Opening of stent cells through the proximal and distal stent struts always increased interslrut distance,but never achieved good apposition to the wall.Balloon diameter increase didn't give proportional enlargement in stent cell diameters.KBI leads to some small better stent positioning,correcting main vessel strut dislodgment from wall,but never gave full strut-wall contact.Distance between struts and wall was minimal only when the stent cell perfectly faced ostium of SB.This was also our observation that the shape of ostium of SB becomed eUiptically-bean shaped after stent implantation and generally kept that shape during consequent stages of experiment.Measured diameter and area stenosis were perfectly fitted and theoretically predicted from our concept Conclusion We have described stent-wall deformations in stent-balloon technique for treatment of coronary bifurcation demonstrating carina displacement as possibly main mechanism of side branch compromise after main vessel stenting.We have shown that KBI could not give full strut-wall contact if there is no perfect facing of stem cell and SB ostium.(J Geroatr Cardool 2008;5(1):43-49) 展开更多
关键词 CORONARY BIFURCATION bench test STENT
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A versatile test bench for photomultiplier tube characterization and its application in the DAMPE-PSD 被引量:3
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作者 Yong Zhou Zhi-Yu Sun +4 位作者 Yu-Hong Yu Yong-Jie Zhang Fang Fang Jun-Ling Chen Bi-Tao Hu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2016年第3期145-152,共8页
Performance characterization for massive photomultiplier tubes(PMTs) is a frequently encountered procedure in large nuclear and particle experiments.To facilitate this work,a dedicated test bench system has been devel... Performance characterization for massive photomultiplier tubes(PMTs) is a frequently encountered procedure in large nuclear and particle experiments.To facilitate this work,a dedicated test bench system has been developed at the Institute of Modern Physics,Chinese Academy of Sciences.The two-dimensional photocathode position scanning capability is an intrinsic function of the test bench,and up to 25 PMTs,with the diameter smaller than 2",can be tested simultaneously.The parameters of the light source pulses can be adjusted in a wide range,thus making it suitable for various characteristics measurements.The test bench system is highly automated with all the controlling operations integrated into a single software.Additionally,the hardware platform is extensible which allows complex testing schemes,and the modularity in the software design makes the migration from one testing configuration to another light-weight and efficient.All these features make the test bench versatile and reusable in different experiments.It has been first used in the construction of the Plastic Scintillator Detector(PSD) of DArk Matter Particle Explorer(DAMPE),and a total of 570 Hamamatsu R4443 tubes were tested successfully.The performance was verified and the testing results are also reported in this article. 展开更多
关键词 试验台架系统 光电倍增管 通用性 特性 性能试验台 中国科学院院士 测试方案 粒子探测器
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The Efficiency Improving of Traction Drive Test Bench with Supercapacitor Energy Storage System
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作者 Genadijs Zaleskis Viesturs Brazis 《Journal of Mathematics and System Science》 2012年第9期570-575,共6页
For development of passenger electrical transport, it is necessary to use energy more rationally. One of methods of vehicle power efficiency increase is installation of on-board energy storage systems. For studying of... For development of passenger electrical transport, it is necessary to use energy more rationally. One of methods of vehicle power efficiency increase is installation of on-board energy storage systems. For studying of system operation, it is necessary to carry out a lot of experiments, therefore it is favorable to use the test bench and its computer model for reduction of the number of physical experiments. In this article, the results of computer modeling for the optimization of traction drive test bench by adjusting of the operation parameters of supercapacitor energy storage are described. Test bench operation is considered in cases of the energy storage system working at various selected supercapacitor initial voltages. Maximal increase of possibility of vehicle test bench regenerative braking with minimal decrease of autonomous power supply mode possibility is investigated. There is estimated the energy storage system efficiency improving measures dependence from supercapacitor operational voltage ranges. Parameters at which the minimum losses of energy are observed are revealed. Dependence of energy storage system discharge power on the most admissible supercapacitor current is established. 展开更多
关键词 Energy storage SUPERCAPACITOR test bench computer modeling passenger electrical transport.
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Laboratory Test Bench for Research Network and Cloud Computing
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作者 Evgeniy Pluzhnik Evgeny Nikulchev Simon Payain 《International Journal of Communications, Network and System Sciences》 2014年第7期243-247,共5页
At present moment, there is a great interest in development of information systems operating in cloud infrastructures. Generally, many of tasks remain unresolved such as tasks of optimization of large databases in a h... At present moment, there is a great interest in development of information systems operating in cloud infrastructures. Generally, many of tasks remain unresolved such as tasks of optimization of large databases in a hybrid cloud infrastructure, quality of service (QoS) at different levels of cloud services, dynamic control of distribution of cloud resources in application systems and many others. Research and development of new solutions can be limited in case of using emulators or international commercial cloud services, due to the closed architecture and limited opportunities for experimentation. Article provides answers to questions on the establishment of a pilot cloud practically “at home” with the ability to adjust the width of the emulation channel and delays in data transmission. It also describes architecture and configuration of the experimental setup. The proposed modular structure can be expanded by available computing power. 展开更多
关键词 CLOUD COMPUTING LABORATORY test bench
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Test Bench for Robotics and Autonomy: Overview and Test Results
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作者 Andrea Merlo Andrea Biggio +1 位作者 Giuseppe Casalino EnricaZereik 《Journal of Mechanics Engineering and Automation》 2013年第6期378-386,共9页
In this paper, the TAS-I (Thales Alenia Space-Italy) Test Bench for Robotics and Autonomy (TBRA) is presented. It is based on a flexible and modular software architecture (Framework Engine), in which each functi... In this paper, the TAS-I (Thales Alenia Space-Italy) Test Bench for Robotics and Autonomy (TBRA) is presented. It is based on a flexible and modular software architecture (Framework Engine), in which each functional module (representing the GNC subsystems) implements a key functionality of the GNC (Guidance Navigation and Control). Modules communicate by means of standardised interfaces designed for exchange of necessary information among the modules composing the entire system. This approach permits the interchange-ability of each subsystem without affecting the overall functionalities of the GNC system. In this paper, the TBRA system, together with the implemented functional modules will be described. Tests results will be reported and future development will be discussed. 展开更多
关键词 Autonomous exploration rover test bench for robotics and autonomy framework engine.
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铰链分布数量对机械弹性车轮力学特性的影响
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作者 林棻 朱晓龙 +2 位作者 赵又群 刘轩江 臧利国 《机械工程学报》 北大核心 2026年第2期344-353,共10页
机械弹性车轮作为一种新型的非充气车轮,具有抗扎、防爆、缓冲减振等优点。由于机械弹性车轮采用独特的悬浮式承载方式,铰链分布数量对车轮的力学特性有着重要影响。基于有限元法建立机械弹性车轮有限元模型,通过负荷特性试验验证了模... 机械弹性车轮作为一种新型的非充气车轮,具有抗扎、防爆、缓冲减振等优点。由于机械弹性车轮采用独特的悬浮式承载方式,铰链分布数量对车轮的力学特性有着重要影响。基于有限元法建立机械弹性车轮有限元模型,通过负荷特性试验验证了模型的有效性。设置多种仿真工况对四种不同铰链分布数量的机械弹性车轮的垂向刚度、侧向刚度和接地特性进行分析,并通过轮胎力学特性试验台对四种不同铰链分布数量的车轮样机进行了力学特性试验。通过仿真进一步分析了铰链分布数量对匹配机械弹性车轮的整车平顺性的影响。结果表明,仿真数据与试验数据具有良好的一致性。随着铰链分布数量的增加,机械弹性车轮的垂向刚度、侧向刚度、接地印迹宽度和最大接地压力均有不同程度的增加,接地印迹长度和接地印迹面积逐渐下降,匹配机械弹性车轮的整车平顺性变差。研究结果为机械弹性车轮的结构优化设计提供了参考。 展开更多
关键词 机械弹性车轮 轮胎力学特性 有限元分析 台架试验
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指夹式油莎豆排种器设计与试验
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作者 赵清来 陈晓明 +2 位作者 赵雨生 王鹏宇 许顺 《吉林农业大学学报》 北大核心 2026年第1期181-188,共8页
针对油莎豆种球表面粗糙且流动性差,难以实现传统机械式排种器单粒精密播种的问题,在油莎豆种球物料特性研究基础上,设计一种指夹式油莎豆排种器。首先,分析排种器的排种过程,明确造成卡种、漏种的原因,确定排种器关键部件结构参数;然后... 针对油莎豆种球表面粗糙且流动性差,难以实现传统机械式排种器单粒精密播种的问题,在油莎豆种球物料特性研究基础上,设计一种指夹式油莎豆排种器。首先,分析排种器的排种过程,明确造成卡种、漏种的原因,确定排种器关键部件结构参数;然后,以粒距合格指数、重播指数和漏播指数为性能指标进行多因素台架试验,明确作业速度、指夹器夹片开口高和倾斜角等因素对各性能指标的影响,以及各因素之间的交互作用对各性能指标的影响;最后,依据台架试验结果优化排种器工作参数,并开展田间试验。田间试验结果表明:理论株距为30 cm时,最优参数组合为指夹器夹片开口高12.0 mm、指夹器夹片倾斜角10°、工作速度4.5 km/h,所得粒距合格指数为95.4%、漏播指数为2.7%、重播指数为1.9%。该指夹式排种器排种性能符合我国农业行业标准,能够满足油莎豆精密播种要求。 展开更多
关键词 油莎豆 排种器 指夹器 台架试验
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轴承台架试验方法在齿轮油中的应用研究
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作者 石啸 雷凌 +2 位作者 黄鑫 尹竟琳 赵心怡 《润滑油》 2026年第1期36-41,共6页
文章聚焦齿轮油轴承润滑保护性能的台架测试体系开展研究,通过分析滚动接触疲劳、微点蚀、白蚀裂纹等典型轴承失效模式,系统对比了不同FE8轴承台架设备的试验方法与评价指标。研究发现:磨损试验侧重摩擦金属表面化学反应膜形成能力的评... 文章聚焦齿轮油轴承润滑保护性能的台架测试体系开展研究,通过分析滚动接触疲劳、微点蚀、白蚀裂纹等典型轴承失效模式,系统对比了不同FE8轴承台架设备的试验方法与评价指标。研究发现:磨损试验侧重摩擦金属表面化学反应膜形成能力的评价,点蚀台架更关注表面疲劳寿命验证,白蚀裂纹测试需模拟特定高速工况下的耐久性能。 展开更多
关键词 齿轮油 轴承 润滑 台架试验
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基于总线的雾液量分布测量试验台的优化试验
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作者 赵尔迪 程睿 +4 位作者 蔡晓华 吴泽全 叶岩 李占成 东忠阁 《农机化研究》 北大核心 2026年第3期129-136,共8页
针对传统喷雾测量中数据延迟、误差较大和参数同步采集效率低等行业痛点,设计了基于CAN总线技术的雾液量分布测量试验台,旨在构建高精度、智能化的喷雾性能测试平台。通过集成CAN总线系统,实现对压力、流量、喷雾角度等核心参数毫秒级... 针对传统喷雾测量中数据延迟、误差较大和参数同步采集效率低等行业痛点,设计了基于CAN总线技术的雾液量分布测量试验台,旨在构建高精度、智能化的喷雾性能测试平台。通过集成CAN总线系统,实现对压力、流量、喷雾角度等核心参数毫秒级同步采集与实时传输,数据处理速度提升50%,测量误差降低至±0.5%,较传统方案显著优化。试验台采用模块化设计,兼容教学演示、科研创新及生产线检测等多元场景,核心优势体现:(1)硬件集成度高,铝合金台架搭载喷杆智能调节系统、ISO标准U型集雾槽及工业视觉模块,确保雾滴收集与图像采集精度;(2)控制智能化,以PLC为核心的电气控制系统,联动试管架翻转机构与自动化数据采集模块,实现从喷雾作业到参数分析的全流程无人化操作。经一致性测试验证,喷头喷量变异系数为1.2%,雾液量变异系数为8.3%,符合标准要求,可精准筛选喷量稳定喷头。 展开更多
关键词 雾液量分布 CAN总线技术 喷头性能测试 数据同步采集 试验台
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油气弹簧激振试验台归一化幅相控制稳定性研究
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作者 齐潘国 韩冬 +1 位作者 迟帅 张辉 《兵器装备工程学报》 北大核心 2026年第3期132-139,190,共9页
针对所研制的油气弹簧激振试验台,在常规幅相控制算法基础上,提出归一化幅相控制算法并深入研究其稳定性问题,以解决试验台幅相控制参数配置复杂的问题。建立某油气弹簧激振试验台液压伺服系统开环传递函数模型,设计P控制参数,保证系统... 针对所研制的油气弹簧激振试验台,在常规幅相控制算法基础上,提出归一化幅相控制算法并深入研究其稳定性问题,以解决试验台幅相控制参数配置复杂的问题。建立某油气弹簧激振试验台液压伺服系统开环传递函数模型,设计P控制参数,保证系统具有足够的稳定裕量。对常规幅相控制算法的结构原理进行深入理论分析,发现算法中的步长增益是影响系统稳定性的决定性因素,且步长增益稳定取值范围与输入正弦幅值相关。提出归一化幅相控制算法,给出唯一的且与输入正弦幅值不相关的步长增益的稳定取值范围。建立某油气弹簧激振试验台归一化幅值控制液压位置伺服系统AMESim仿真模型,仿真验证步长增益对稳定性的影响,仿真结果与理论一致,仿真发现当步长增益临近区间边界值时,系统易产生超调现象,导致稳定性降低。把归一化幅相控制算法应用在所研制的油气弹簧激振试验台,试验验证了仿真结果与理论推导的正确性。 展开更多
关键词 油气弹簧 激振试验台 归一化幅相控制 稳定性 AMESIM
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满足欧Ⅶ排放法规的轻型车制动磨损颗粒物测试装备开发
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作者 谷雨 吕誉 +2 位作者 黄小清 徐辉 曾光 《内燃机工程》 北大核心 2026年第1期48-53,共6页
为了实现欧Ⅶ排放法规对制动磨损颗粒物(brake wear particle,BWP)排放的测试需求,基于联合国全球技术法规第24号(United Nations Global Technical Regulation No.24,UN GTR-24)标准,开发了国内首台满足轻型车BWP排放检测的惯性试验台... 为了实现欧Ⅶ排放法规对制动磨损颗粒物(brake wear particle,BWP)排放的测试需求,基于联合国全球技术法规第24号(United Nations Global Technical Regulation No.24,UN GTR-24)标准,开发了国内首台满足轻型车BWP排放检测的惯性试验台测试系统,并验证了测试系统对UN GTR-24标准的合规性要求。结果表明,该惯性测试实验台的系统级别颗粒背景浓度为:最大流量及最小流量下,直径超过10 nm的总颗粒物数量(记为TPN_(10))及直径超过10 nm的固体颗粒物数量(记为SPN_(10))均为0个/cm^(3)。测试过程中冷却气流温度、湿度和流量均满足UN GTR-24标准的合规性要求;能量耗散偏差低于5%,远低于UN GTR-24标准对能量耗散的合规性要求。BWP排放测试前颗粒背景浓度SPN_(10)为10.1个/cm^(3),TPN_(10)为13.8个/cm^(3);测试后颗粒背景浓度SPN_(10)为7.1个/cm^(3),TPN_(10)为17.3个/cm^(3),均满足UN GTR-24标准要求,证明所开发的BWP测试系统能够用于欧Ⅶ法规开展BWP检测。采用开发的BWP测试系统,对某轻型燃油车的盘式制动器进行的排放测试结果表明,粒径不大于2.5μm的颗粒物(PM_(2.5))质量、粒径不大于10μm的颗粒物(PM10)质量、SPN_(10)和TPN_(10)的排放结果分别为1.6 mg/km、3.9 mg/km、6.03×10^(9)个/km、1.64×10^(10)个/km。 展开更多
关键词 制动器 颗粒物 非尾气颗粒物 欧Ⅶ 测试装备 惯性试验台
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反推装置液压试验台智能测控系统设计
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作者 张熙 杨佳 彭卫东 《内燃机与配件》 2026年第4期63-65,共3页
针对民用飞机反推装置的地面测试需求,设计了一套集成液压驱动与智能测控的试验台系统。该系统采用闭环液压循环架构,通过温控模块、多级过滤及动态压力、流量调节,实现在极端环境下稳定供给液压能;测控系统基于PLC与LabVIEW上位机软件... 针对民用飞机反推装置的地面测试需求,设计了一套集成液压驱动与智能测控的试验台系统。该系统采用闭环液压循环架构,通过温控模块、多级过滤及动态压力、流量调节,实现在极端环境下稳定供给液压能;测控系统基于PLC与LabVIEW上位机软件构建,结合OPC协议实现多参数实时采集与协同控制。在典型工况验证中,系统成功维持反推装置额定工作压力,证明了液压节能设计与温控策略的有效性。所设计的试验台已具备反推装置出厂性能检测与科研验证能力,为适航符合性提供了数据支撑,后续可扩展更多工况联合测试,推动国产民机液压技术自主化进程。 展开更多
关键词 反推装置 测控系统 试验台
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柴油/庚酸甲酯混合燃料颗粒物排放特性研究
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作者 张鑫茹 张鹏 +2 位作者 张书涵 陈昊 吉振华 《内燃机工程》 北大核心 2026年第2期65-75,共11页
为探明柴油中混合高含氧量、来源广泛的清洁燃料庚酸甲酯对颗粒物排放的影响,基于一台四冲程高压共轨柴油机开展台架试验。庚酸甲酯分别按体积比0%、10%、20%与柴油进行掺混(燃料分别记为D100、MH10、MH20)燃烧,采用TSI公司生产的SMPS-3... 为探明柴油中混合高含氧量、来源广泛的清洁燃料庚酸甲酯对颗粒物排放的影响,基于一台四冲程高压共轨柴油机开展台架试验。庚酸甲酯分别按体积比0%、10%、20%与柴油进行掺混(燃料分别记为D100、MH10、MH20)燃烧,采用TSI公司生产的SMPS-3936颗粒物粒径谱仪进行颗粒物排放监测,探究不同负荷、废气再循环(exhaust gas recirculation,EGR)率、喷射策略下燃用D100、MH10、MH203种燃料的颗粒物数浓度和体积分数变化趋势。结果表明:中高负荷时颗粒物数浓度与体积分数显著高于低负荷,颗粒物粒径向大粒径偏移,且庚酸甲酯掺混比例越高,颗粒物数浓度与体积分数越低,且燃用D100、MH10、MH203种燃料时呈现依次递减的规律;EGR率增加导致积聚态颗粒数浓度上升、粒径增大,同时导致颗粒物体积分数变大。掺混庚酸甲酯能大幅度抑制颗粒物的增长。在EGR率为0%和12%时,MH10的颗粒数浓度较D100的颗粒数浓度分别降低74.4%、75.7%,MH20的颗粒数浓度较D100分别降低78.6%、77.6%;双喷模式下增大主预喷间隔角可有效降低颗粒物数浓度,积聚态颗粒降幅显著高于核态颗粒,且掺混庚酸甲酯能进一步减少排放;单次喷射时,随着喷油时刻的推迟,颗粒物总数先降后升,D100核态颗粒变化微弱,积聚态颗粒在上止点前4°最低;MH20在上止点前6°时排放控制最优,且颗粒物体积分数随喷油推迟整体呈下降趋势。研究表明,掺混庚酸甲酯能显著降低颗粒物排放水平。 展开更多
关键词 台架试验 庚酸甲酯 掺混燃烧 颗粒物排放
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ABS与RBS集成控制试验平台地面制动力模拟研究
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作者 史品佳 王辉 +1 位作者 吕立亚 闵永军 《机械设计与制造》 北大核心 2026年第3期125-130,共6页
为实现车辆ABS与RBS集成控制试验中地面制动力随滑移率变化的准确模拟,设计了一种地面制动力动态模拟控制系统。该系统能够根据车辆滑移率的变化控制磁粉离合器传递扭矩,模拟不同路面实时可变的地面制动力。基于车辆ABS与RBS集成控制试... 为实现车辆ABS与RBS集成控制试验中地面制动力随滑移率变化的准确模拟,设计了一种地面制动力动态模拟控制系统。该系统能够根据车辆滑移率的变化控制磁粉离合器传递扭矩,模拟不同路面实时可变的地面制动力。基于车辆ABS与RBS集成控制试验平台,开展了单一路面和跃变路面地面制动力模拟控制试验。试验结果表明,设计的磁粉离合器控制器不仅在单一路面制动试验时体现出响应迅速、跟踪性能好、稳态误差小的特点,同时在跃变路面试验时也具有较好的适应性。所设计的地面制动力模拟系统能够动态模拟实际的地面制动力,具有一定的工程应用价值。 展开更多
关键词 地面制动力 ABS与RBS集成控制 磁粉离合器 模糊自适应PID控制 台架试验
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基于IAN-LLE的轴箱轴承性能退化评估
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作者 宫保贵 张兴武 陈雪峰 《振动.测试与诊断》 北大核心 2026年第1期197-202,225,共7页
为评估轴箱轴承性能退化状态,提出一种改进的自适应邻域局部线性嵌入方法(improved adaptive neighborhood locally linear embedding,简称IAN-LLE),用以准确评估轴箱轴承性能的退化趋势与严重程度。首先,利用余弦相似度(cosine similar... 为评估轴箱轴承性能退化状态,提出一种改进的自适应邻域局部线性嵌入方法(improved adaptive neighborhood locally linear embedding,简称IAN-LLE),用以准确评估轴箱轴承性能的退化趋势与严重程度。首先,利用余弦相似度(cosine similarity,简称CS)确定初始领域参数;其次,运用高斯核概率估计密度和流行曲率对初始领域参数进行修正;然后,构建融合退化指标(fusion degradation index,简称FDL),用以评估轴箱轴承的退化性能;最后,为验证该指标的有效性,分别开展轴承全寿命试验和轴箱轴承台架试验。结果表明:所提出的FDL具有较高的准确性,可用于评估轴箱轴承的性能变化。 展开更多
关键词 自适应邻域局部线性嵌入方法 退化评估 轴箱轴承 台架试验
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试验台工装拓扑优化及尺寸优化设计
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作者 汪炯藤 阳光武 +3 位作者 肖守讷 朱涛 杨冰 蔡松岑 《机械强度》 北大核心 2026年第3期60-67,共8页
【目的】拓扑优化是一种当前使用较为普遍的优化方法,其通过优化材料构造,在给定的设计空间和约束条件下找到结构设计的最优形状、实现轻量化和满足约束条件。基于变密度拓扑优化法的思想,以某试验台工装结构为分析对象,阐述了建立拓扑... 【目的】拓扑优化是一种当前使用较为普遍的优化方法,其通过优化材料构造,在给定的设计空间和约束条件下找到结构设计的最优形状、实现轻量化和满足约束条件。基于变密度拓扑优化法的思想,以某试验台工装结构为分析对象,阐述了建立拓扑优化的数学模型及求解方法,以期为基于先进设计方法的结构设计提供参考。【方法】首先,在HyperMesh仿真软件中采用OptiStruct模块创建工装有限元模型,以最小质量和最大1阶频率为优化目标,对单工况下的工装结构进行拓扑优化及尺寸优化,合理布置材料分布及优化板件厚度,提高工装设计质量;其次,根据优化结果及制造加工实用性,设计新的工装结构;最后,在Nastran模块中按照GB/T 21563—2018标准对工装模型进行强度校核。工装结构完成实际加工后,将其置于振动台上,分别实施纵向、横向与垂向扫频试验,随后将试验结果与仿真结果进行对比。【结果】结果表明,1阶模态频率从766 Hz提升至1 009 Hz,提高了31.72%;同时,工装质量从51 kg降至44.26 kg,减轻13.24%,且强度符合设计标准,整体达到了预期的优化目标。 展开更多
关键词 试验台工装 拓扑优化 尺寸优化 模态分析 强度校核
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