Kinetic models of natural gas combustion in an internal combustion engine

In this study, combustion of methane was simulated using four kinetic models of methane in CHEMKIN 4.1.1 for 0-D closed internal combustion （IC） engine reactor. Two detailed （GRIMECH3.0 ＆ UBC MECH2.0） and two reduced （One step ＆ Four steps） models were examined for various IC engine designs. The detailed models （GRIMECH3.0, ＆ UBC MECH2.0） and 4-step models successfully predicted the combustion while global model was unable to predict any combustion reaction. This study illustrated that the detailed model showed good concordances in the prediction of chamber pressure, temperature and major combustion species profiles. The detailed models also exhibited the capabilities to predict the pollutants formation in an IC engine while the reduced schemes showed failure in the prediction of pollutants emissions. Although, there are discrepancies among the profiles of four considered model, the detailed models （GRIMECH3.0 ＆ UBC MECH2.0） produced the acceptable agreement in the species prediction and formation of pollutants.

An approach for IC engine coolant energy recovery based on low-temperature organic Rankine cycle

To promote the fuel utilization efficiency of IC engine, an approach was proposed for IC engine coolant energy recovery based on low-temperature organic Rankine cycle(ORC). The ORC system uses IC engine coolant as heat source, and it is coupled to the IC engine cooling system. After various kinds of organic working media were compared, R124 was selected as the ORC working medium. According to IC engine operating conditions and coolant energy characteristics, the major parameters of ORC system were preliminary designed. Then, the effects of various parameters on cycle performance and recovery potential of coolant energy were analyzed via cycle process calculation. The results indicate that cycle efficiency is mainly influenced by the working pressure of ORC, while the maximum working pressure is limited by IC engine coolant temperature. At the same working pressure, cycle efficiency is hardly affected by both the mass flow rate and temperature of working medium. When the bottom cycle working pressure arrives at the maximum allowable value of 1.6 MPa, the fuel utilization efficiency of IC engine could be improved by 12.1%.All these demonstrate that this low-temperature ORC is a useful energy-saving technology for IC engine.

Optical Fiber Pyrometer Applied in IC Engine

Based on the theory of thermal radiation,a contact type optical fiber pyrometer applied in IC engine is put forward.It is composed of three parts:a blackbody probe,optical system,electrical process system.The key technology of design is discussed.Experiment is given to prove that the pyrometer has much higher responsive speed,distinguishability and much longer running life than other pyrometers.

DYNAMIC DESIGN OF INTERNAL COMBUSTION ENGINE BLOCK STRUCTURE

Several main steps of internal combustion engine block structure dynamic design,such as model set up,structure dynamic response analysis,optimizing design and vibration and noise control,are discussed for the type of EQ6100 gasoline engine block

Optimization of Transducer Location for Novel Non-Intrusive Methodologies of Diagnosis in Diesel Engines

The health monitoring has been studied to ensure integrity of design of engine structure by detection,quantification,and prediction of damages.Early detection of faults may allow the downtime of maintenance to be rescheduled,thus preventing sudden shutdown of machines.In cylinder pressure developed,vibrations and noise emissions data provide a rich source of information about condition of engines.Monitoring of vibrations and noise emissions are novel non-intrusive methodologies for which positioning of various transducers are important issue.The presented work shows applicability of these diagnosis methodologies adopted in case of diesel engines.The effects of changing various fuel injection parameters was analyzed.Scope of using non-intrusive technique has been analyzed by changing locations of microphone.Novelty of this worklies in exploring signal processing methods for various locations around the engine test set up.Various frequency ranges of contributing noise and vibration sources were identified.Time-Frequency analysis showed the onset of various cyclic.Based on the identification of various frequency bands,it is possible to device suitable filters in order to extract more information.

STATE ENGINEERING RESEARCH CENTERS OF THE CAS (Ⅱ)

State Engineering Research Center for Asic Design The National Engineering Research Center for ASIC Design is a national base for ASIC analysis and design.Its current research area includes:IC analysis/design methods,system development and application and commercial IC chip analysis. The center was established on the basis of the Microelectronic Design Center of Institute of Automation of the Chinese Academy of Sciences. As a pool of intelligent and technical resource,many researchers and experts on IC analysis/design and computer software/

基于PSPICE喷油器电磁阀双电源双边驱动电路的设计与优化研究

为了提高喷油器电磁阀的高速驱动性能,建立了精确的电控柴油机电磁阀驱动模块的PSPICE模型,据此仿真分析了驱动方式和续流方式、驱动电压及续流回馈电压对电磁阀开启、关闭响应性影响规律。设计了电磁阀双电源双边驱动钳压续流电路,进行了工作过程的数学分析和参数优化。试验结果表明:该驱动电路提高了各个通道的喷油一致性,小油量(0.5ms喷油脉宽)时各驱动通道的最大偏差率为2.21%,相对标准差为1.41%,同时五次喷油下缸压峰值波动率为0.57%,该驱动电路满足高效清洁燃烧系统对喷油器驱动控制精度和各缸喷油规律一致性的要求。

基于GPS与IC卡数据的公交站点匹配方法

一票制(单次刷卡)公交线路IC卡数据中缺少乘客上车站点信息,为获得乘客上车站点信息,需要将IC卡交易数据与公交站点进行匹配。首先根据公交车辆GPS数据和公交IC卡数据分别推算站点间运行时间,建立匹配约束规则完成首次站点匹配,并求得公交车辆GPS系统与公交IC卡收费系统的时间平均偏差值,再将时间平均偏差嵌入数据匹配模型,利用禁忌搜索算法对其他未匹配的交易记录进行二次匹配。为作比较,数据试验还包括仅根据站点间运行时间对GPS和IC卡数据进行匹配,从而找到IC卡交易记录与公交站点对应关系。数据试验表明:在GPS数据较完整的条件下,该方法能够精确实现IC卡交易记录与上车站点的匹配,而对比试验方法的匹配精度为80%,低于本文所研究方法。

基于公交IC卡数据的乘客出行分类研究

为得到体现公交乘客出行时空规律的数据,采用基于出行链方法推导出公共汽车乘客的下车站点;建立了描述单个乘客多天出行的完整数据框架;根据乘客参加不同活动所产生的出行时空特征定义了3类出行:通勤类出行、普通类出行和随机类出行,将出行频次与出发时间的标准差作为分类标准对公交乘客出行进行分类。研究表明:39.1%的乘客具有普通类或通勤类出行,生成总客流的76.4%;60.9%的乘客只具有随机类出行,生成总客流的23.6%。通过对乘客出行的分类研究可以更好地掌握乘客公交出行的规律和需求。

基于GPS和IC卡数据的公交出行OD推算方法

主要基于GPS和公交IC卡数据研究推算交通小区公交出行OD的一种方法。将居民公交出行分为闭合型出行链和非连续型公交出行链,通过数据的挖掘融合技术,结合居民公交出行规律推算交通小区的公交OD矩阵,利用站点吸引强度对无明显规律的紊乱出行数据进行修正,提出了基于GPS和公交IC卡数据推算公交出行交通小区OD的方法,并以佛山市中心城区为例验证推算方法的可靠性。研究表明:所得公交出行OD矩阵精度较高。

TEMIC系列射频卡及其应用

介绍了TEMIC公司射频卡系列的特点、工作原理和使用方法,并就实际的使用经验,对软硬件的一些问题做了简要的叙述。

基于分布式中间件ICE的应用架构研究

在分布式系统中,分布式平台之间的差异增加了开发的复杂性。基于一种轻量级的分布式中间件ICE,提出了在分布式异构环境中的一般架构模型。该模型可以降低模块之间的耦合度,解决服务器负载过大的问题。将该模型应用到网络安全管理系统中,解决了网络安全管理系统中平台差异问题和服务器负载均衡问题。

基于IC卡和RBF神经网络的短时公交客流量预测

在公交客流量特性分析基础上,通过IC卡获取了实时公交客流量数据;结合GPS数据,利用OD反推法分析了实时客流分布;进而建立了基于IC卡和RBF神经网络的短时公交客流量预测模型并介绍了具体预测过程。对重庆市841公交线路进行了实例分析,得到上下车客流真实值与预测值的平均绝对相对误差均小于1.5%,实例计算结果表明该模型能获取实时客流数据,预测精度高,具有一定的实际应用价值。

内循环厌氧反应器(IC)的应用与发展

从工程实践的角度对IC反应器的应用与研究现状进行了介绍,并对IC反应器在工程应用中暴露出来的问题进行了详细分析,最后指出了IC反应器的研究发展趋势,表明IC反应器具有产业化的发展前景。

基于IC卡信息的居民公交出行动态特性

通过对公交IC卡数据库中大量数据的筛选和处理,分析了不同公交乘客群体的性别、年龄构成,绘制了工作日、双休日及节假日公交客流的时间分布曲线,重点研究了客流高峰时段的居民公交出行特性。提出了基于公交IC卡信息的若干指标,定量分析了公交客流量在一天营运时间内的变动,在一个月中以星期为周期的律动以及一年中各月客流量的波动等动态特性,揭示了城市居民公交出行的基本规律,可为城市公交政策的制定、公交系统规划和运营管理提供可靠的理论依据和实用参数。

IC封装成型过程关键力学问题

随着电子行业的发展,对IC封装过程中的Au丝变形提出越来越严格的要求,不能出现断Au丝、露Au丝以及Au丝与芯片接触的现象。基于Ansys/Workbench有限元分析软件,将流场与压力场进行耦合,针对在不同注塑压力下,对同一条带YOA2的Au丝进行应力变形分析,并且用X射线对封装后的模块进行检测。模拟结果与检测结果相比较表明:当注塑压力从6 MPa增大到8 MPa时,Au丝变形量只增大了16μm,而且Au丝变形与压力呈线性关系。采用X射线检测与CAE技术相结合,研究封装过程中Au丝受力变形,并提出相应改进方案,对改善Au丝变形具有一定意义。

基于GBDT算法的地铁IC卡通勤人群识别

随着公交IC卡的应用和普及,从IC卡数据中挖掘通勤用户,为下阶段采取分流措施缓解早晚高峰压力,优化票价制定等具有重要意义。以广州市地铁数据为依托,选取合适的特征属性,提出了一种基于梯度提升树(gradient boosting decision tree,GBDT)机器学习算法为基础的通勤人群识别方法。首先以周工作日的首末次平均刷卡时间、首末次平均刷卡时长、首末次刷卡时长波动程度、刷卡次数总和等5个特征来制定调查问卷的数据格式。然后利用处理过的带标签(通勤/非通勤)的调查问卷数据去训练GBDT分类器模型,测试样本的通勤识别的准确率高达94.16%。最后利用该模型对广州地铁IC卡数据通勤人群进行识别,结果显示广州地铁刷卡数据中通勤人群数量为131万左右,占总地铁刷卡出行人数32%左右。

基于IC卡数据的长距离公交客流特征分析

围绕长距离公交客流时空特征,基于公交IC卡数据,提出以时间不均衡指数、高峰时间占比、方向不均衡指数、沿线公交资源密度、线路平均里程利用系数5项指标构建评价体系,选取4条京冀长距离公交线路进行案例分析并给出评价雷达图。研究表明:建立的指标体系可有效量化分析评价长距离公交的客流特征,进而对其运营管理提供优化建议。案例计算结果可以看出中心城区长距离公交各项评价指标均小于城区外部公交;815等通勤比重大的跨市域线路公交里程利用率、不均衡性较高,可采用区间车或直达车等调度方式;对于915等资源密度小、里程利用率低的线路,可适当优化线网,调整站点。

智能IC卡管理系统在农村软体沼气工程中的应用

在现有的沼气工程项目中,由于没有一种合适的管理模式和收费模式,造成沼气能源的二次浪费。为减少这种现象的发生,提出了以IC卡为管理核心来管理农村沼气供气过程中的收费。该系统通过主控制器对母卡进行参数设定,母卡对子控制器进行参数传递和控制。用户使用前要进行预充值,然后通过刷卡的方式使用沼气,使用完后重复进行充值。通过这种方式,实现了农村沼气工程的合理收费和有序管理,并且避免了沼气能源的二次浪费。

基于公交IC卡数据的区域公交压力指数研究

公共交通系统在运行中产生的IC卡刷卡及车辆运行GPS数据为量化描述区域公交系统的压力提供了数据支持。基于公交系统在运行中产生的大量的GPS数据和IC卡刷卡数据,选取了包括满载率、停靠时间、单位时间内的进、出站量和地铁剩余运能等压力模型的评价指标,基于加权平均理论建立了地面公交及地铁压力指数模型;根据公交及地铁站点的等级及登降量因素提出了不同类型站点的权重系数阈值;取地面公交和地铁站压力均值建立了区域公交运行压力模型,并划分了压力分级体系。最后以北京市的国贸和东单区域为例进行了压力指数的计算,分析了两区域压力指数差异的时间及空间原因,并提取2个区域的实际公交登降量数据对压力指数进行了验证,证明该压力指数模型能够有效反映公交系统的运行压力。