薄膜型LNG船晃荡冲击局部强度分析建模方法研究

为保证薄膜型LNG船(No96型)的营运安全,除绝缘箱外,还有必要对晃荡冲击载荷作用下船体结构进行局部强度分析.考虑到分析对象的不同,同时为了简化有限元模型和降低船体结构局部分析的计算工作量,针对船体结构局部强度分析中绝缘箱建模范围,树脂绳模拟方式以及绝缘箱网格基本尺寸提出了建议并进行了可行性验证.研究表明,建议方法可以在满足计算精度的前提下,极大减少船体结构局部强度分析的工作量,可为晃荡冲击载荷作用下薄膜型LNG船(No96型)船体结构局部强度分析及相关规范制定提供有效的参考.     

厚度对变截面钢板弹簧应力分布的影响

为了研究在相同厚度比下不同的根部厚度,以及在相同根部厚度下不同的厚度比对变截面钢板弹簧应力分布的影响,建立变截面钢板弹簧的1/2有限元模型.结果表明,随着钢板弹簧厚度的增加,应力分布越均匀;而随着厚度比的减小,应力分布越均匀.但是厚度比越大,其对应力分布的影响越小.用合适的厚度与厚度比对某一种钢板弹簧总成优化,通过对比分析,验证厚度对变截面钢板弹簧应力分布的影响.     

铁路通信MSTP传输系统FE接口应用的探讨

随着铁路业务信息化的不断发展,各类业务对铁路通信MSTP传输系统FE接口的需求越来越多,本文结合实例,从业务需求、接口类型、数据配置等方面对MSTP传输系统FE接口的应用进行探讨。     

单元尺寸对内燃机模态计算精度的影响

从数学理论出发分析了有限元求解精度的影响因素 ,并从工程角度探讨了单元尺寸的选择对复杂内燃机零部件及整机模态计算精度的影响 ,得出的结论可为类似结构模态计算时单元类型及尺寸的选择提供参考。     

Development and performance analysis of an automotive power seat for disabled persons

As the number of disabled people grows, independence and mobility become a priority for those individuals. To achieve this goal, a ‘Turny-type power seat’ was developed in this study to assist a disabled person rise from a vehicle without trouble. The design and modeling of the power seat were performed using AutoCAD and CATIA software. The major motions of the power seat system are swiveling, sliding, and extending, which are accomplished primarily by DC motors, chains, and gears. Most of the power seat parts were made from mild steel. Welding technology was used throughout the frame fabrication. To ensure the safety and stability of the power seat, various tests were performed, and the results analyzed. The static analysis of the power seat was carried out by ANSYS 11.0. The results showed that the power seat conformed to the Americans with Disabilities Act (ADA) standards. The durability test was performed by repeatedly rotating and sliding the power seat under loading conditions. Dynamic crash simulation was carried out using the LS-DYNA software. The durability test ensured a longer life of the power seat, while the crash analysis showed a small rotational distortion that was not harmful to passengers. However, the front seat had a slightly larger forward displacement, which was not comfortable for passengers. Therefore, further modifications of the power seat should be done to improve the performance, with attention given to the reduction of the forward displacement in the event of a crash.     

Durability improvement of automotive V-belt pulley

Improving the durability of an automotive V-belt pulley, which is commonly used in an automotive powertrain to transfer power to other parts, is discussed. Fatigue life of the original V-belt pulley is predicted based on damage analysis by finite element analysis (FEA). Stress history of the pulley during operation was found by performing consecutive static analyses on the pulley as the pulley rotates. Assembly load (due to the tightening of the bolts) and operation load were considered to describe the actual load conditions in a durability test. The contact condition from the belt was calculated and applied to the surface of the pulley. Static analyses at 36 different positions of the pulley, every ten degrees of rotation, were performed to determine the stress history of the pulley during operation. Using stress history data calculated from FE analysis, damage over one rotation of the pulley was calculated and fatigue life, in number of rotations to failure, was estimated. An improvement to the durability of the pulley was investigated by modifying the design of the pulley using FE analysis results. Durability tests for the pulleys used in the analysis were carried out to verify the analytical results. Comparison between analysis and experimental results showed that analytical results correlated with the experimental results closely.     

横向分段施工预应力混凝土斜箱梁的模型试验研究

根据工程实际需要,提出横向分段施工预应力混凝土斜箱梁结构的施工方式,并对此施工方式的箱梁桥和整体浇筑的箱梁桥进行模型试验研究与有限元计算。通过各种工况的试验加载,及对实测得到的试验数据（挠度和应变）数理统计、图表分析比较和相应的有限元分析,定量比较了两者的受力性能差异,即混凝土开裂前,横向分段施工预应力混凝土斜箱梁的挠度比整体浇筑斜箱梁的挠度约大5．3％,纵向应变比整体浇筑斜箱梁的纵向应变大13．5％,湿接缝的纵向应变是整体浇筑施工斜箱梁的纵向应变的59％。横向分段施工预应力混凝土斜箱梁截面上存在着预应力的应力重分布,此重分布应力对湿接缝的混凝土受拉变形产生了抑制作用,且现有的有限元通用程序尚无法计算此应力重分布值的大小、     

G325九江大桥主桥斜拉桥静载试验分析

九江大桥位于国道325线南海段,全长1675.2m,通航主跨为2×160m的独塔双索面竖琴形斜拉桥。介绍该桥静载试验成果,并结合有限元理论分析,将计算结果与试验结果对比,对该桥的结构现状进行评定。     

高速公路波形梁护栏改造方案研究

通过有限元模拟方法依托京珠南(广州至太和段)扩建罩面工程研究了原护栏加高方案的防撞性能,提出了3种能满足目前我国评价标准要求的波形梁护栏改造方案,适合应用于目前状况下我国的高速公路波形梁护栏改造及再利用。     

基于无缝线路失稳分析的地铁轨温预警限值

运用有限元方法建立直线和曲线有砟轨道无缝线路的稳定性分析模型,讨论道床横向阻力、线路初始不平顺等多个因素的影响,分析结果表明:当钢轨横向位移超过0.5 mm左右时,其增长的速率明显加大。因此建议综合考虑钢轨横向位移增长速率突变处的温升、我国规定的允许温升及计算温升作为高温时的轨温预警限值,并采取绿-黄-橙-红四级预警机制。