CIMS环境下汽车覆盖件模具CAPP系统的开发和应用

介绍了汽车覆盖件模具CAPP系统的功能和结构,提出了在开发模具CAPP系统中需要注意的一些问题。     

汽车冷冲压模的模块化设计

针对汽车冷冲压模具实体化、参数化设计存在的问题，利用CATIA CAD／CAM一体化实体设计软件，采取模块化设计方法完成了冷冲压模具的实体设计，弥补了CATIA CAD实体设计的不足。以海狮牌汽车后门上右加强件的冲压模具设计为例，详细介绍了采用该软件进行模具结构设计的过程。     

永磁涡流调速技术在风机水泵调速中的适用性分析

本文分析了永磁涡流调速技术应用在风机水泵类负载中,滑差功率损耗与转速的关系。推导出永磁涡流调速装置啮合长度与临界转差率、最大转矩的公式。通过对比分析风机水泵类负载的特性曲线与永磁涡流调速传动装置的转矩-转速特性曲线,得出了永磁涡流调速装置使用时会产生转速突变,传递的转矩不能满足风机水泵负载的要求。     

多工位级进模的结构设计与故障排除

阐述了级进模排样、镶块、模板及其它零件的设计过程,指出了级进模设计中应注意的事项,介绍了模具使用中一些常见故障和解决办法。     

Experimental investigation of nozzle cavitating flow characteristics for diesel and biodiesel fuels

This study was performed to clarify criteria for cavitation inception and the relationship between flow conditions and cavitation flow patterns of diesel and biodiesel fuels. The goal was to analyze the effects of injection conditions and fuel properties on cavitating flow and disintegration phenomena of flow after fuel injection. To accomplish this goal, it was utilized a test nozzle with a cylindrical cross-sectional orifice and a flow visualization system composed of a fuel supply system and an image acquisition system. In order to analyze the rate of flow and injection pressure of the fuel, a flow rate meter and pressure gauge were installed at the entrance of the nozzle. A long distance microscope device equipped with a digital camera and a high resolution ICCD camera were used to acquire flow images of diesel and biodiesel, respectively. The effects of nozzle geometry on the cavitating flow were also investigated. Lastly, a detailed comparison of the nozzle cavitation characteristics of both fuel types was conducted under a variety of fuel injection parameters. The results of this analysis revealed that nozzle cavitation flow could be divided into four regimes: turbulent flow, beginning of cavitation, growth of cavitation, and hydraulic flip. The velocity coefficient of diesel fuel was greatly altered following an increase in flow rate, although for biodiesel, the variation of the velocity coefficient relative to the rate of flow was mostly constant. The cavitation number decreased gradually with an increase in the Reynolds number and Weber number, and the discharge coefficient was nearly equal to one, regardless of cavitation number. Lastly, it could not observe cavitation growth in the tapered nozzle despite an increase in fuel injection pressure.     

设缝圆形浅池池壁空间内力分析及优化计算

该文结合工程实例,对设完全缝圆形浅池池壁在内水压力下的内力情况进行了有限元空间内力分析计算,在此基础上给出了一个简单的拟合计算公式,供设计人员设计时参考。     

基于绕行系数的交通可达性研究

为了评价不同路网形态下的城市道路可达性和对出行者的出行方式选择的影响,通过引入绕行系数的概念,对不同路网密度和交通管理策略的案例研究,说明可达性的变化对交通方式选择的影响。提出了基于绕行系数的可达性分析的基本思路,研究结果表明：仅以出行距离作为交通方式选择的影响要素条件下,可达性的改善有利于非机动出行方式分担率提高,合理的城市路网密度和适当的交通管理策略有利于多种交通方式共同发展。     

双重可调式轨道基础研究与设计

自动化轨道吊由于行驶速度远超港区普通轨道吊,因此其运行精度要求及标准较高。需研究如何根据实际情况选择可行、可靠、经济的轨道基础结构形式并合理确定相关参数。通过比选目前常用轨道基础形式,结合洋山工程实例及有限元数值模拟,提出了一种不设桩基的新基础形式——双重可调式轨道基础,并完善了其结构及构造设计,基本解决了沉降易发地基上不设桩基的轨道吊设备安全高效运行问题。     

下行式移动模架现浇32m客运专线双线箱梁施工技术

结合石太客运专线采用移动模架现浇32m双线整孔简支箱梁的工程实践,介绍了下行式移动模架的设计、拼装、预压、混凝土浇筑施工、预应力张拉、过孔等施工技术。     

水中圆形钢板桩围堰施工技术

南京长江隧道工程右汊大桥为独塔自锚式悬索桥,主塔基础（10号）在水中,为14φ2．5m钻孔桩,桩长87m,主塔承台为八角形,横桥向总宽度20．7m,顺桥向总宽度19．226m,厚5m。结合工程实际,主塔承台采用圆形钢板桩围堰施工,圆满完成了承台的施工。