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This work developed a computational methodology to evaluate and compare standard fire exposures such as those outlined in ASTM E119 with real fire exposures and determine the difference in the temperature rise of a rail car floor assembly. The real fire exposures simulated in this work were identified in a review of incidents and consisted of a constantly-fed diesel fuel spill, a localized trash fire, and a gasoline spill simulated from a collision of the railcar with an automobile. These realistic fire exposures were applied to a variety of exemplar rail cars representative of single-level and bi-level passenger cars. These floor assembly models exposed to realistic fires were simulated in Fire Dynamics Simulator (FDS). The thermal exposure at the underside of railcar provided by FDS was coupled with a thermal model in ABAQUS, which provided the evolution of temperature in different components of the floor assembly. The standard scenarios were simulated for 2 hours instead of the typical 30 minutes to identify the appropriate exposure duration in ASTM E119, which can better represent a real fire scenario. The average and maximum temperatures predicted at the unexposed surface for both scenarios were compared with the threshold values given in NFPA 130. 相似文献
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In the early design stage, automotive modeling should both meet the requirements of aesthetics and engineering. Therefore, a vehicle CAD (computer aided design) model that can be easily adjusted by feedbacks is necessary. Based on CE-Bézier surface, this paper presents a set of algorithms for parametric segmentation and fairing surface generation in a car model. This model is defined by a simplified automotive template and relevant control points, shape parameters and segmentation parameters, which can be modified to alter the car form efficiently. With this model and the corresponding adjustment method, more than fifty various vehicle models are established in this research according to different parameters. And two methods for calculating similarity index between car models are constructed, which are suitable for brand design trend analysis and modelling design decisionmaking. 相似文献
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本文介绍了欧洲轿车新战略决策,也即:将要提高轿车的电池电压,,阻燃材料的比率和工作温度;Synolite5001-T-1牌聚酯树脂的阻燃防炎性能优于酚醛树脂。 相似文献
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论文介绍了一种针对铁水鱼雷罐车铁水液位检测的较为可行的低成本方案。采用车上间接称重、远红外非接触传输信号方式,解决了对移动铁水罐车进行实时监测的难题。 相似文献
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预应力钢-混凝土组合梁的应用与研究 总被引:1,自引:0,他引:1
回顾了预应力钢 混凝土组合梁国内外应用与研究历史 ,分析了现有规范及理论的不足 ,并指出了有待解决的问题。 相似文献
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All parameters related to car energy were investigated in this work, and the power basics of a car design powered by solar energy are laid down. Year-round weather conditions, car weight, road roughness and road inclination were taken as variable parameters used to calculate the car speed and working hours (year round). Fixed parameters taken for the design were: a photovoltaic generator area of 6 m2, car length of 5 m, car width of 1.8 m and maximum power output of 480 W/person with a maximum of two persons. These parameters depended on the regulations of “Tour de Sol '91”. Calculations depended on Amman weather conditions. Sixteen ASI 16-200 ARCO SOLAR INC. model photovoltaic modules were used, with three DELCO 1150 lead acid batteries connected to a permanent magnet DC motor of 0.8 hp. This car can run at different speeds 3–6 hours/day on 200 days/year. 相似文献
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介绍了XC型车号自动识别系统的工作原理及在轨道衡的应用,解决了长期以来轨道衡路用车车号和自重依靠人工抄录易出错及劳动强度大的问题。 相似文献
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对于采用连锁经营的汽车零件销售企业来说,各经营网点分布在同一城市的不同区域或不同城市,为了在充分利用原有信息和资源的基础上处理好许多中间环节,减少人员工作量,保证企业销存状态良好,提高管理效率,设计了基于B/S模式的汽车零件销存管理信息系统的技术方案,详细讨论系统的功能设计以及实现技术。 相似文献