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A reduced combustion mechanism of ammonia/diesel optimized with multi-objective genetic algorithm

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Defence Technology（防务技术） 2024年第4期34卷 187-200页

作者： wanchen sun Shaodian Lin Hao Zhang Liang Guo Wenpeng Zeng Genan Zhu Mengqi Jiang State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130025China

For the deep understanding on combustion of ammonia/diesel,this study develops a reduced mechanism of ammonia/diesel with 227 species and 937 *** sub-mechanism on ammonia/interactions of N-based and C-based species(N—C)/NOx is optimized using the Non-dominated Sorting Genetic Algorithm II(NSGA-II)with 200 *** optimized mechanism(named as 937b)is validated against combustion characteristics of ammonia/methane(which is used to examine the accuracy of N—C interactions)and ammonia/diesel *** ignition delay times(IDTs),the laminar flame speeds and most of key intermediate species during the combustion of ammonia/methane blends can be accurately simulated by 937b under a wide range of *** for ammonia/diesel blends with various diesel energy fractions,reasonable predictions on the IDTs under pressures from 1.0 MPa to5.0 MPa as well as the laminar flame speeds are also achieved by *** particular,with regard to the IDT simulations of ammonia/diesel blends,937b makes progress in both aspects of overall accuracy and computational efficiency,compared to a detailed ammonia/diesel *** kinetic analysis reveals that the reaction pathway of ammonia during the combustion of ammonia/diesel blend mainly differs in the tendencies of oxygen additions to NH_2 and NH with different equivalence ratios.

关键词： Ammonia Diesel Combustion Kinetic mechanism Multi-objective optimization

Morphological Development of Fuel Droplets after Impacting Biomimetic Structured Surfaces with Different Temperatures

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Journal of Bionic Engineering 2020年第4期17卷 822-834页

作者： Liang Guo Yuheng Gao Ningning Cai Degang Li Yuying Yan wanchen sun State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130022China School of Management Jilin UniversityChangchun 130022China Faculty of Engineering University of NottinghamNottingham NG72RDUK

To improve the controllability for the evaporation process of fuel spray impinging on the cylinder wall,an experimental study on the development of morphological process of different fuel droplets on aluminium alloy surfaces is carried *** metal surfaces with different wettability are prepared by laser etching and chemical etching for the *** total,three different fuels are tested and compared under different surface temperatures,including diesel,n-butanol and dimethyl carbonate(DMC).The results show that under a lower wall temperature,the surface wettability,viscosity and surface tension of the fuels have significant effects on spreading and rebounding behaviour of the *** the wall temperature rises over the boiling points of the fuel but below its Leidenfrost temperature,the contact angles between the fuels and surfaces are varying according to the surface wettability,boiling point and Leidenfrost temperature of the *** the temperature of the surface exceeds the Leidenfrost temperature of all the fuels,after impacting the surfaces,different fuel droplets tend to have the same development pattern,regardless of the surface *** rebound level is mainly affected by the amount of fuel vapour generated during the wall-hitting ***,surface tension and other properties of the fuel have little effect on post-impacting behaviour of the droplet when the wall temperature is higher than the Leidenfrost temperature of the fuel.

关键词： fuel droplets wettability dynamic contact angle rebound factor biomimetic

Evaporation Characteristics and Morphological Evolutions of Fuel Droplets After Hitting Different Wettability Surfaces

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Journal of Bionic Engineering 2023年第2期20卷 734-747页

作者： Yanling Chen Liang Guo Ningning Cai wanchen sun Yuying Yan Degang Li Han Wang Rong Xuan State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130025China School of Business and Management Jilin UniversityChangchun130012China Faculty of Engineering University of NottinghamNottinghamNG72RDUK

To solve the wall-wetting problem in internal combustion engines,the physical and chemical etching methods are used to prepare different wettability surfaces with various *** evaporation characteristics and morphological evolution processes of diesel and n-butanol droplets after hitting the various surfaces are *** results show that the surface microstructures increase the surface roughness(Ra),enhancing the oleophilic property of the oleophilic *** with n-butanol droplets,the same surface shows stronger oleophobicity to diesel *** a droplet hits an oleophilic property surface with a lower temperature,the stronger the oleophilicity,the shorter the evaporation *** oleophilic surfaces,larger Ra leads to a higher Leidenfrost temperature(TLeid).The low TLeid caused by enhanced oleophobicity,dense microstructures and increased convex dome height facilitates droplet rebound and promotes the evaporation of the wall-impinging droplets into the *** evaporation rate of the droplets is not only related to the characteristics of the solid surfaces and the fuel droplets but also affected by the heat transfer rate to the droplets in different boiling *** spreading diameter of a droplet on an oleophobic surface varies significantly less with time than that on an oleophilic surface under the same surface temperature.

关键词： Fuel droplets Wettability Evaporation time Leidenfrost temperature Morphological evolutions

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基于机器学习的中医体质分类研究

中国医疗设备 2024年第1期39卷 6-11页

作者：潘康宁王洪杰于霞孙万晨威海市妇幼保健院医疗设备科山东威海264200 威海市妇幼保健院超声二科山东威海264200 威海市胸科医院医务科山东威海264200

目的采用随机森林的过滤式特征选择方法,筛选出最优特征子集后构建梯度提升决策树(Gradient Boosting Decision Tree,GBDT)模型,对平和体质与偏颇体质进行分类研究。方法选取2756例受试者为研究对象,使用横断面调查法进行问卷调查。... 详细信息

目的采用随机森林的过滤式特征选择方法,筛选出最优特征子集后构建梯度提升决策树(Gradient Boosting Decision Tree,GBDT)模型,对平和体质与偏颇体质进行分类研究。方法选取2756例受试者为研究对象,使用横断面调查法进行问卷调查。采集受试者十二经脉上24个原穴的穴位信号与身高、体重、年龄、性别等信息构建数据集。对数据集预处理后使用随机森林特征选择方法筛选最优特征子集;使用GBDT算法构建基于机器学习的平和-偏颇体质二分类研究;采用十折交叉验证计算准确度、精准度、召回率、F1得分,并综合评价模型性能。结果筛选出22个特征构成最优特征子集,使用筛选后的特征子集构建的GBDT模型准确度、精准度、召回率、F1得分分别是92.86%、93.65%、93.08%、0.92。结论随机森林的特征选择方法有助于筛选最优特征子集,GBDT可为中医体质分类研究提供帮助。

关键词：机器学习中医体质特征选择分类模型

Numerical investigation of flow unsteadiness and heat transfer on suction surface of rotating airfoils within a gas turbine cascade

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Propulsion and Power Research 2017年第2期6卷 91-100页

作者： Liang Guo Yuying Yan wanchen sun Jie Zhu State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130022China Fluids&Thermal Engineering Research Croup.Faulty of Engineering University of Nottingham.Nottingham NG72RDUnited Kingdom

The effects of the periodical turbulence and pressure fluctuation on suction surface heat transfer over airfoils of a row of rotor blades with a certain type have been investigated numerically in this *** calculation is perfomed using v^(2)-f model with the numerical results of pressure fluctuation and heat transfer performance over 4 sample points being analyzed and compared with existing experimental *** shows that the static pressure change has significant impact on heat transfer performance of the fore suction surface,especially in the active region of the shock waves formed from the trailing edge of upstream ***,for the rear suction surface,the flow turbulence contributes more to the heat transfer change over the surface,due to the reduced pressure oscillation through this *** shifted phenomenon across the surface can be observed for both pressure and heat transfer parameters,which should be a result of turbulence migration and wake passing across the airfoil.

关键词： Gas turbinecascade Water ramjet Flow unsteadiness Pressure fluctuation Heat transfer Blade suctionsurface

Piezotronic neuromorphic devices:principle,manufacture,and applications

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International Journal of Extreme Manufacturing 2024年第3期6卷 363-385页

作者： Xiangde Lin Zhenyu Feng Yao Xiong Wenwen sun wanchen Yao Yichen Wei Zhong Lin Wang Qijun sun Department of Research Shanghai University of Medicine and Health Sciences Affiliated Zhoupu HospitalShanghai 201318People’s Republic of China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400People’s Republic of China Center on Nanoenergy Research School of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004People’s Republic of China Shandong Zhongke Naneng Energy Technology Co. LtdDongying 257061People’s Republic of China Georgia Institute of Technology AtlantaGA 30332-0245United States of America

With the arrival of the era of artificial intelligence(AI)and big data,the explosive growth of data has raised higher demands on computer hardware and *** techniques inspired by biological nervous systems are expected to be one of the approaches to breaking the von Neumann *** neuromorphic devices modulate electrical transport characteristics by piezopotential and directly associate external mechanical motion with electrical output signals in an active manner,with the capability to sense/store/process information of external *** this review,we have presented the piezotronic neuromorphic devices(which are classified into strain-gated piezotronic transistors and piezoelectric nanogenerator-gated field effect transistors based on device structure)and discussed their operating mechanisms and related manufacture ***,we summarized the research progress of piezotronic neuromorphic devices in recent years and provided a detailed discussion on multifunctional applications,including bionic sensing,information storage,logic computing,and electrical/optical artificial ***,in the context of future development,challenges,and perspectives,we have discussed how to modulate novel neuromorphic devices with piezotronic effects more *** is believed that the piezotronic neuromorphic devices have great potential for the next generation of interactive sensation/memory/computation to facilitate the development of the Internet of Things,AI,biomedical engineering,etc.

关键词： piezotronics neuromorphic devices strain-gated transistors piezoelectric nanogenerators synaptic transistors

基于深度学习的医疗器械不良事件风险类型的研究

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中国医学工程 2024年第8期32卷 34-37页

作者：潘康宁袁明辉赵玉娟玄怡王茜王洪杰孙万晨威海市妇幼保健院医疗设备科山东威海264200 威海市食品药品检验检测研究院山东威海264200 山东省药品不良反应监测中心山东济南250000 威海市胸科医院医务科山东威海264200

目的探讨深度学习相关技术在医疗器械不良事件风险类型判别中的应用价值。方法选取自2023年4月至9月国家医疗器械不良事件监测系统数据库中的12350条数据为研究对象,每条数据具有25个维度的信息,其中包括企业、注册证号、产品批号、不... 详细信息

目的探讨深度学习相关技术在医疗器械不良事件风险类型判别中的应用价值。方法选取自2023年4月至9月国家医疗器械不良事件监测系统数据库中的12350条数据为研究对象,每条数据具有25个维度的信息,其中包括企业、注册证号、产品批号、不良事件描述等。采用fastText技术将文本特征转化为向量表示,采用k均值聚类方法将具有相似主题或语义内容的文本数据分组到同一类别中,搭建BP神经网络将不良事件的风险类型分为轻微危害、严重危害、死亡。结果该研究选取的深度学习方法能够很好地处理文本数据且搭建的BP神经网络模型的准确度(accuracy)为92.86%,精密度(precision)为93.65%,召回率(recall)为93.08%,F1-score为92.31%,曲线下面积(AUC)为0.98,具有良好的准确性和泛化能力。结论基于深度学习的医疗器械不良事件风险类型的研究可有效地为医疗器械不良事件监测工作提供帮助。

关键词：深度学习医疗器械不良事件分类研究

Characteristics of Particle Size Distributions About Emissions in A Common-rail Diesel Engine with Biodiesel Blends

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Characteristics of Particle Size Distributions About Emissio...

煤基合成燃料及其在汽车发动机上的应用与技术进展

2011 2nd International Conference on Challenges in Environmental Science and Computer Engineering(CESCE 2011)

作者： An Puzun sun wanchen Li Guoliang Tan Manzhi Lai Chunjie Chen Shibao National Laboratory of Automobile Dynamic Simulation Jilin University

Test of particle size distributions are carried out by using the TSI3090 EEPSTM particle size spectrometer and a twostage dilution system on a high-pressure common rail diesel *** of the particle size distributions reveals the physical and chemical characteristics of the biodiesel *** results show that sizes of particle emissions are mostly below *** size of biodiesel fuel is a bimodal distribution with the number of the nucleation mode accounting for more than 60%of the total *** the proportion increase of biodiesel,the number of particles in nucleation mode increases while the accumulation mode particles with a size>50nm decreases and the peak area shifts to the small particle *** size distributions of the petroleum diesel show a single peak between 5000nm region and majority of the particles shows accumulation *** load has great impact on the particle size distribution,as the load increases the proportion of the nucleation mode decreases.

关键词： Diesel engine biodiesel / diesel blended fuels Particle size distribution

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汽车安全与节能学报 2021年第1期12卷 1-17页

作者：孙万臣蒋梦奇汽车仿真与控制国家重点实验室吉林大学中国长春130025

随着汽车保有量不断增加,能源安全和低碳化发展日益受到国内外的广泛关注,鉴于中国富煤、贫油、少气的能源结构,基于煤炭Fischer–Tropsch合成工艺制取的煤基合成燃料因其良好的燃烧和排放特性已成为汽车理想的替代燃料。煤基合成燃料... 详细信息

随着汽车保有量不断增加,能源安全和低碳化发展日益受到国内外的广泛关注,鉴于中国富煤、贫油、少气的能源结构,基于煤炭Fischer–Tropsch合成工艺制取的煤基合成燃料因其良好的燃烧和排放特性已成为汽车理想的替代燃料。煤基合成燃料在汽车等动力机械上的推广应用,对于实现汽车能源多元化、减少中国石油对外依存度、实现煤炭资源的高效清洁利用、降低汽车排放污染物具有重要的战略意义和应用价值。该文介绍了煤基合成燃料的生产、合成工艺关键技术以及发展历程;基于众多研究者关于煤基合成燃料的相关研究成果,阐述了煤基合成柴油用于内燃机燃料的喷雾、混合、燃烧及排放特性;总结并预测了煤基合成燃料市场化应用存在的问题和未来发展趋势,为煤基合成燃料的推广及在内燃机上的高效清洁应用提出了合理建议。

关键词：煤基合成燃料理化特性燃烧排放