公交大巴涡轮增压器替换方案的可行性分析与实施

目前在公交大巴柴油发动机上主要是采用安装废气涡轮增压装置的方法来提高发动机功率。但是在许多情况之下，由于使用年限问题、驾驶员操作不当或其他原因，往往出现发动机基本正常却需要更换废气涡轮增压器。本文正是为了解决上述问题而来。“废气涡轮增压器的替换”是一种较为经济、合理的解决方案，值得相关从业人员参考。     

Structural Optimization of Hatch Cover Based on Bi-directional Evolutionary Structure Optimization and Surrogate Model Method

Weight reduction has attracted much attention among ship designers and ship owners. In the present work, based on an improved bi-directional evolutionary structural optimization (BESO) method and surrogate model method, we propose a hybrid optimization method for the structural design optimization of beam-plate structures, which covers three optimization levels: dimension optimization, topology optimization and section optimization. The objective of the proposed optimization method is to minimize the weight of design object under a group of constraints. The kernel optimization procedure (KOP) uses BESO to obtain the optimal topology from a ground structure. To deal with beam-plate structures, the traditional BESO method is improved by using cubic box as the unit cell instead of solid unit to construct periodic lattice structure. In the first optimization level, a series of ground structures are generated based on different dimensional parameter combinations, the KOP is performed to all the ground structures, the response surface model of optimal objective values and dimension parameters is created, and then the optimal dimension parameters can be obtained. In the second optimization level, the optimal topology is obtained by using the KOP according to the optimal dimension parameters. In the third optimization level, response surface method (RSM) is used to determine the section parameters. The proposed method is applied to a hatch cover structure design. The locations and shapes of all the structural members are determined from an oversized ground structure. The results show that the proposed method leads to a greater weight saving, compared with the original design and genetic algorithm (GA) based optimization results.     

油泵注油排气装置的研制与应用

目前汽车维修排除空气最常用的做法是人工排气法和高压气抽油排气法。而本文详细介绍了一种油泵注油排气装置的研制与应用。     

基于XML的船体结构CAD数据交换研究

分析了XML技术在船体结构数据信息交换应用中的特点,归纳了船体结构在计算机里的数据表达形式,并建立了相应的XML Schema.分别为船体结构设计软件CATIA和Intelliship设计了XML交换接口,基于XML文件格式,实现了不同CAD系统之间的船体结构数据交换.     

半潜坐底式海上风电安装船设计与开发

适用于海上浅水区域作业的半潜坐底式海上风电安装船具有安全性好、施工效率高和成本低等特点,其设计的特殊性在于需要考虑海流冲蚀泥沙导致的坐底面积丧失。以开发的一艘典型实船为例,阐述主要功能,提出坐底稳定性应考虑的两种工况,采用有限元计算对坐底工况结构强度进行校核,对在软泥和粉砂两种地质条件下进行作业给出应对措施,可为同类型船的设计提供一定技术参考。     

东风天锦货车异响并冒黑烟故障排除1例

<正>故障现象有1辆东风天锦载货车,搭载康明斯B170 33柴油发动机,行驶里程约为10万km。用户反映:载货车中、高速行驶时排气管排黑烟。怠速行驶烟色不明显,重载爬坡无力、黑烟大。检修过程起动发动机,手动操纵加速杆,发动机中、高速黑烟明显。发动机轰鸣声中夹杂"噗、噗、噗"声,像工业空压机工作时那种连贯的声音。拆掉进气空滤听更明显、清脆。依次松掉喷油泵端高压油管接头,逐一"断缸",     

Research on marine structure inspection support system on mobile device platform

Ship and offshore structure often work in very severe environment. Therefore routine inspection and maintenance are essential to keep ship structure and equipment in good state, and can decrease the possibility of sea pollution and safety problems. Besides that, the activity of inspection and maintenance is also directly connected with cost control and condition assessment. Current inspection is still mainly based on paper and pen, so it is rather time-consuming for transferring inspection data from paper to computer system, and more difficult to make calculation based on the inspection records. In this paper, the concept of information integration model and inspection support system using mobile device is introduced. The structuralized data in the information integration model offer much convenience to data transferring. The inspection support system consists of one headquarter management subsystem and one inspector handling subsystem. A mechanism of data exchange between the two subsystems is developed based on standard inspection workflow. The headquarter subsystem works on computer, and the inspector subsystem is mobile application instead of paper and pen. Versatile tests and platform experiments are carried out to demonstrate and confirm the feasibility and validity.     

基于本体的船舶机舱布置设计方法研究

针对船舶机舱布置智能化程度低、设计知识难以继承与共享的特点,将本体理论引入到机舱布置领域,并探讨了有关机舱布置智能化设计的相关内容。提出了基于本体的机舱布置设计方法框架,运用本体建模软件Protégé实现了框架中的部分功能,并通过实例验证了本体的一致性、通用性与有效性,构建了基本的查询、推理与扩展机制,以便于在进一步的研究中整合网络资源,实现设计知识继承共享,为船舶机舱布置辅助设计程序的开发奠定基础。     

基于人工神经网络的船型设计与阻力预报

船舶阻力与船体形状之间的关系是复杂的非线性关系,在实际设计中预报船舶阻力的方法一般主要有经验公式法和CFD方法.从打破传统方法的局限性和避免CFD计算的高成本出发,考虑人工神经网络理论对处理非线性复杂问题具有良好的适应性,采用RBF神经网络,试图为不同设计阶段的需要提出新的船型设计方法,并建立了相应的船型-阻力性能预测模型.通过实际数据验证了此方法的可行性和实用性.