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Asymptotic Analysis Soot Model and Experiment for a Directed Injection Engine

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 1011-1015页

作者： LIU Yongfeng PEI Pucheng xiong qinghui LU Yong Beijing Engineering Research Center of Monitoring for Construction Safety Beijing University of Civil Engineering and Architecture Beijing 100044 China State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China Science and Technology on Vehicle Transmission Laboratory China North Vehicle Research Institute Beijing 100072 China

The existing soot models are either too complex and can not be applied to the internal combustion engine, or too simple to make calculation errors. Exploring the soot model becomes the pursuit of the goal of many researchers within the error range in the current computer speed. On the basis of the latest experimental results, TP （temperature phases） model is presented as a new soot model to carry out optimization calculation for a high-pressure common rail diesel engine. Temperature and excess air factor are the most important two parameters in this model. When zone temperature T〈 1 500 K and excess air factor Ф〉0.6, only the soot precursors-- polycyclic aromatic hydrocarbons（PAH） is created and there is no soot emission. When zone temperature T ≥ 1 500 K and excess air factor Ф〈0.6, PAHs and soot source terms （particle inception, surface growth, oxidation, coagulation） are calculated. The TP model is then implemented in KIVA code instead of original model to carry out optimizing. KIVA standard model and experimental data are analyzed for the results of cylinder pressures, the corresponding heat release rates, and soot with variation of injection time, variation of rail pressure and variation of speed among TP models. The experimental results indicate that the TP model can carry out optimization and computational fluid dynamics can be a tool to calculate for a high-pressure common rail directed injection diesel engine. The TP model result is closer than the use of the original KIVA-3V results of soot model accuracy by about 50% and TP model gives a new method for engine researchers.

关键词： high-pressure common rail diesel engine soot optimization calculation

Research on Pressure Characteristics of a Vehicle Shift Hydraulic System Based on AMESim

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Research on Pressure Characteristics of a Vehicle Shift Hydr...

基于MOSA算法的高压共轨喷油器多目标仿真优化设计

第36届中国控制会议

作者： Qihui Zhang Wei xiong Haitao Wang Guangfeng Guan Zuwen Wang qinghui xiong Ship Electromechanical Equipment Institute DaLian Maritime University Vehicle Transmission Key Laboratory China North Vehicle Research Institute

ISBN: (纸本)9781538629185

Hydraulic system of vehicle shift is an important part of the vehicle automatic shift control *** affects the quality of the *** order to research the characteristics of the hydraulic system of vehicle shift,a model was established based on *** correctness of the simulation model is verified by building a single hydraulic circuit test *** and experiment show that the system can shift in 1,03 s,and the shift process is stable and has good shift quality.

关键词： AMESim Pressure Characteristics Vehicle Shift Hydraulic System

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农业机械学报 2011年第1期42卷 27-30页

作者：熊庆辉张幽彤北京理工大学机械与车辆学院北京100081

建立了高压共轨喷油器的Matlab/Simulink仿真模型,采用多目标模拟退火MOSA优化算法作为寻优策略,以针阀开启延迟和关闭延迟为目标函数进行高压共轨喷油器的关键结构参数多目标仿真优化设计。实验结果表明:优化后的高压共轨喷油器针阀开... 详细信息

建立了高压共轨喷油器的Matlab/Simulink仿真模型,采用多目标模拟退火MOSA优化算法作为寻优策略,以针阀开启延迟和关闭延迟为目标函数进行高压共轨喷油器的关键结构参数多目标仿真优化设计。实验结果表明:优化后的高压共轨喷油器针阀开启延迟时间降低16.7%,达到0.25 ms;关闭延迟时间降低15.2%,达到0.78 ms。

关键词：喷油器高压共轨模拟退火多目标优化

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大流量压电式喷油器设计与试验

农业机械学报 2011年第11期42卷 10-14页

作者：王军熊庆辉张幽彤装甲兵工程学院机械工程系北京100072 北京理工大学机械与车辆学院北京100081

分析了大功率柴油机喷油流量要求,提出了压电喷油器主要部件的设计参数。结合实际发动机,确定了大流量压电式喷油器的设计方案,计算了两种压电堆和液力放大机构的输出参数,确定了双排不同喷孔直径的布置方案;通过试验分析压电执行器的... 详细信息

分析了大功率柴油机喷油流量要求,提出了压电喷油器主要部件的设计参数。结合实际发动机,确定了大流量压电式喷油器的设计方案,计算了两种压电堆和液力放大机构的输出参数,确定了双排不同喷孔直径的布置方案;通过试验分析压电执行器的响应速度,确定了喷油器最小喷射间隔时间为0.6 ms,经喷油器喷油效果验证表明:压电执行器、液力放大机构和双排喷孔的方案能满足大流量喷油的要求。

关键词：柴油机喷油器压电晶体设计试验

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压电式高压共轨喷油系统喷油量波动特性试验

农业机械学报 2010年第7期41卷 11-14页

作者：丁晓亮张幽彤熊庆辉北京理工大学机械与车辆学院北京100081

研究了压电式高压共轨喷油系统多次喷射过程中影响主喷油量波动的因素,采用EFS IFR8420型单次喷射仪对预喷和主喷的油量及喷油速率进行精确测量,总结了主喷油量波动的影响因素及其变化规律:预喷油量越小、主预间隔时间越短,主喷油量波... 详细信息

研究了压电式高压共轨喷油系统多次喷射过程中影响主喷油量波动的因素,采用EFS IFR8420型单次喷射仪对预喷和主喷的油量及喷油速率进行精确测量,总结了主喷油量波动的影响因素及其变化规律:预喷油量越小、主预间隔时间越短,主喷油量波动幅度越大,且随着主预间隔时间的增加,主喷油量呈周期性波动且波动幅度逐渐衰减。通过试验确定了预喷产生的压力波动是导致主喷油量波动的主要原因,为后续的多次喷射控制策略的设计和主喷油量的压力波动修正提供了可靠的试验数据。

关键词：压电喷油器高压共轨油量波动

Clinical Evaluation of Hepatic Fibrosis in Chinese Patients with Nonalcoholic Fatty Liver Disease with FibroScan

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Chinese Medicine 2015年第2期6卷 115-123页

作者： Zeli Gao Xiaoli Lin Guoyu Chen Jieru Ji Mingfeng Tang Xiaotong He qinghui xiong Ming Li Department of Gastroenterology People’s Hospital of Pudong New Area Shanghai China Laboratory of Innovative Medicine Hong Kong

Aim: The clinical value of FibroScan in evaluation of hepatic fibrosis was assessed in Chinese patients with nonalcoholic fatty liver disease (NAFLD). Methods: Liver stiffness and other NAFLD related variables were measured in NAFLD patients with either elevated or normal hyaluronic acid (HA) levels, and in healthy volunteers respectively. Moreover, hepatic fibrosis rat model was used for the correlation analysis between the measured liver elasticity and its corresponding pathological changes. Results: The severity of NAFLD in patients was positively correlated with both HA level and FibroScan values suggesting that fibrosis occured along with the progression of NAFLD. Interestingly, the FibroScan value was found to change at an earlier stage of the disease than that of HA level. The mean liver elasticity in the sampling volume of the region of interest in experimental rats, which were subject to the induction of liver fibrosis using peritoneal injection of carbon tetrachloride (CCl4) for 6 or 9 weeks respectively, was measured using Fibroscan. The examination of pathological changes of these experimental rats demonstrated the positive correlation of the measured elasticity values with the extent (severity) of the corresponding pathological changes in the rats of 6 weeks post induction of liver fibrosis with a moderate liver fibrosis, or 9 weeks with a severe liver fibrosis. The average liver stiffness for the normal liver (S0) was 4.51 ± 0.82 kPa, for moderate liver fibrosis (S2) was 6.91 ± 1.32 kPa, and for severe liver fibrosis (S3) 9.62 ± 1.82 kPa. Conclusion: FibroScan can be used to objectively and quantitatively identify the trend in the changing stiffness of the liver and noninvasively detect the development of liver fibrosis.

关键词： FibroScan Nonalcoholic Fatty Liver Disease Hyaluronic Acid Ultrasound Elastography

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车辆换档用2D数字缓冲阀的研究

机械工程学报 2018年第20期54卷 206-212页

作者：张啟晖熊伟阮健关广丰熊庆辉王祖温江西理工大学机电工程学院大连海事大学船舶机电装备研究所浙江工业大学特种装备制造与先进加工技术教育部重点实验室中国北方车辆研究所车辆传动重点实验室

传统的车辆换档液压缓冲阀主要依靠节流小孔以及弹簧的相互作用来控制离合器内油液的压力,使其在一段时间内缓慢的上升,但其调节灵活度低,适应性较差,为此首次提出采用2D数字技术应用于车辆换档缓冲领域,设计2D数字缓冲阀,利用2D数字先... 详细信息

传统的车辆换档液压缓冲阀主要依靠节流小孔以及弹簧的相互作用来控制离合器内油液的压力,使其在一段时间内缓慢的上升,但其调节灵活度低,适应性较差,为此首次提出采用2D数字技术应用于车辆换档缓冲领域,设计2D数字缓冲阀,利用2D数字先导阀芯产生的推力推动主阀芯运动,进而控制缓冲阀出口的油液压力。介绍2D数字缓冲阀的结构和工作原理,并建立2D数字缓冲阀的数学模型,利用Matlab和AMESim对其模型进行联合求解,最后进行仿真分析和试验研究。研究结果表明:2D数字缓冲阀的线性度为9.25%,滞环为0.106;2D数字缓冲阀输出油压实现了换档过程中离合器内油压的变化要求,其缓冲特性的控制精度达到10.52%;缓冲阀的仿真和试验结果趋势是一致的,验证了联合仿真模型的正确性。

关键词：换档缓冲阀 2D数字阀缓冲特性

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压电作动器驱动两级电液比例减压阀设计分析

哈尔滨工业大学学报 2017年第7期49卷 46-51页

作者：杨庆俊汪俊龙吕庆军熊庆辉哈尔滨工业大学流体控制与自动化系哈尔滨150080 车辆传动国防科技重点实验室(北京理工大学) 北京100072

针对以往采用压电作动器的减压阀必须采用压力传感器的不足,提出一种先导式比例减压阀.该阀采用压电作动器控制先导阀阀口开度,与先导供油器的固定节流孔形成分压作用,实现对先导压力的控制,进而控制主阀实现对主阀出口压力控制.对减压... 详细信息

针对以往采用压电作动器的减压阀必须采用压力传感器的不足,提出一种先导式比例减压阀.该阀采用压电作动器控制先导阀阀口开度,与先导供油器的固定节流孔形成分压作用,实现对先导压力的控制,进而控制主阀实现对主阀出口压力控制.对减压阀进行结构和原理分析,建立数学模型;用Simulink仿真分析结构参数对静动态特性的影响.采用调零弹簧将最低可控压力向下扩展到0;设计三台肩式阀芯结构,通过流场分析验证了该结构有效地减小液动力;根据仿真结果选择恰当的反馈阻尼孔尺寸,保证减压阀的动态特性.所设计的减压阀无须测量压力并闭环即可实现减压功能,具有良好的调压范围、调压精度,能实现快速稳定动态响应.

关键词：压电作动器比例减压阀数学模型三台肩式阀芯动态特性

Self-assembled monolayers(SAMs)in inverted perovskite solar cells and their tandem photovoltaics application

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Interdisciplinary Materials 2024年第2期3卷 203-244页

作者： Zijun Yi Xin Li Yuchen xiong Guibin Shen Wenguang Zhang Yihuai Huang qinghui Jiang Xin Ren Ng Yubo Luo Jianghui Zheng Wei Lin Leong Fan Fu Tongle Bu Junyou Yang State Key Laboratory of Material Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhanChina China‐Eu Institute for Clean and Renewable Energy Huazhong University of Science and TechnologyWuhanChina School of Electrical and Electronic Engineering Nanyang Technological UniversitySingaporeSingapore Department of Chemistry National University of SingaporeSingaporeSingapore School of Physics The University of SydneySydneyNew South WalesAustralia Laboratory for Thin Films and Photovoltaics Empa‐Swiss Federal Laboratories for Materials Science and TechnologyDübendorfSwitzerland State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhanChina

Self-assembled monolayers(SAMs)employed in inverted perovskite solar cells(PSCs)have achieved groundbreaking progress in device efficiency and stability for both single-junction and tandem configurations,owing to their distinctive and versatile ability to manipulate chemical and physical interface *** this regard,we present a comprehensive review of recent research advancements concerning SAMs in inverted perovskite singlejunction and tandem solar cells,where the prevailing challenges and future development prospects in the applications of SAMs are *** thoroughly examine the mechanistic roles of diverse SAMs in energy-level regulation,interface modification,defect passivation,and charge *** is achieved by understanding how interfacial molecular interactions can be finely tuned to mitigate charge recombination losses in inverted *** this comprehensive review,we aim to provide valuable insights and references for further investigation and utilization of SAMs in inverted perovskite single‐junction and tandem solar cells.

关键词： inverted perovskite solar cells power conversion efficiency self-assembled monolayers tandem