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排序方式: 共有850条查询结果,搜索用时 281 毫秒
711.
This paper analyzes the influence of transient operating modes in the Cat 3512B-HD and MTU 4000 R41 locomotive diesel engines on their energy usage. This analysis represents an integral component of the technological research and development performed at Lietuvos Geležinkeliai AB (JSC Lithuanian Railways) with the objective of increasing the efficiency of freight transportation with the upgraded 2M62M and modern ER20CF/2ER20CF diesel locomotives. The influence of transient modes on the operating variables of the locomotive diesel engines was evaluated under operational load-cycling conditions to aid in the selection of appropriate parameters (e.g., the train weight, the diesel locomotive type, and the technical characteristics of the diesel locomotive to be modeled) for freight transportation on Lithuanian railway lines. It was determined that the engine’s electronic control system compensates for the negative effects of transient operations on the engine’s energy usage. As a result, the increase in fuel consumption is less than 3% during transient operation when compared to steady-state operation. Through this research, methodological foundations have been formulated and adapted for the use of the mathematical modeling of the transient modes of locomotive diesel engines to optimize freight transportation, resulting in an expected decrease of 10–15% in fuel consumption. 相似文献
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某型汽轮发电机组公共底座模态分析及试验 总被引:1,自引:0,他引:1
对某船用汽轮发电机组公共底座进行了模态仿真分析,并进行了模态测试。测试结果与仿真分析结果达到了吻合,说明公共底座有限元建模方法可行,有限元模型满足工程精度要求,这为进一步分析整体汽轮发电机组动力特性奠定了基础。 相似文献
715.
对无功功率进行有效补偿以提高电能利用率是电力系统的核心问题。详细阐述了无功补偿的作用和相关技术的发展历程,分析了各类补偿方法的特点和存在的问题,并对无功补偿技术的发展及其在船舶电力系统中的应用趋势进行了展望。 相似文献
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陈新梅 《武汉船舶职业技术学院学报》2013,(1):22-24,29
本文从节能的角度出发,研究了中小型柴油机掺烧重柴油的可行性。作者选取具有代表性的2135型柴油机做掺烧重柴油的试验。根据实验结果对柴油机掺烧重柴油后的负荷特性和排放特性的进行了分析,结果表明中小型柴油机掺烧重柴油可行。 相似文献
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Raj Bridgelall 《运输规划与技术》2013,36(8):711-737
Parking demand is a significant land-use problem in campus planning. The parking policies of universities and large corporations with facilities located in small urban areas shape the character of their campuses. These facilities will benefit from a simplified methodology to study the effects of parking availability on transportation mode mix and impacts on recruitment and staffing policies. This paper, based on a case study of North Dakota State University in the United States, introduces an analytical framework to provide planners with insights about how parking supply and demand affects campus transportation mode choice. The methodology relies only on aggregate mode choice data for the special generator zone and the average aggregate volume/capacity ratio projections for all external routes that access the zone. This reduced data requirement significantly lowers analysis cost and obviates the need for specialized modelling software and spatial network analysis tools. Results illustrate that the framework is effective for analysing mode choice changes under different scenarios of parking supply and population growth. 相似文献
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介绍了常用的柴油机状态监测技术,阐述了船舶柴油机在线监测与故障诊断系统的组成及主要功能,实现了基于多状态参数的柴油机综合监测与故障诊断,对提高船舶柴油机可靠性、保障船舶运行安全具有重要意义。 相似文献