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在山路和平路上,进行了不同载荷下国V柴油车的实际道路行驶排放(RDE)试验.采集车速、海拔、氮氧化物(Nox)和颗粒物数量(PN)排放浓度等数据,分析了道路坡度、车辆载荷与输出功率对排放的影响.研究发现:测试柴油车辆,在平均坡度约6%山路行驶时Nox排放因子高于平路20%以上,PN低于平路20%以上.道路坡度自0增大到... 相似文献
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电动空气压缩机为纯电动物流车提供压缩气源,以供整车制动及辅助用气装置的使用.文章基于整车性能的受影响程度进行电动空气压缩机布置的多方案分析,从多个维度进行客观评价,选取适合于整车的最优方案.此方法亦可用作其他关键件的布置校核. 相似文献
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消声器内部流场及其对消声性能影响 总被引:2,自引:0,他引:2
在自行设计建造的消声器静态试验台上,对某型消声器在有、无气流两种情况下进行了试验研究,并根据试验进行了消声器内部流场CFD仿真研究。研究表明,气流在一定的速度范围内对消声器消声量影响很小,当超出范围时消声量随气流速度的增大而减小,同时消声器压力损失也加大。说明流速和内部结构是影响消声器性能的重要因素。 相似文献
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Currently, the shipping industry is facing a great challenge of reducing emissions. Reducing ship speeds will reduce the emissions in the immediate future with no additional infrastructure. However, a detailed investigation is required to verify the claim that a 10% speed reduction would lead to 19% fuel savings (Faber et al., 2012).This paper investigates fuel savings due to speed reduction using detailed modeling of ship performance. Three container ships, two bulk carriers, and one tanker, representative of the shipping fleet, have been designed. Voyages have been simulated by modeling calm water resistance, wave resistance, propulsion efficiency, and engine limits. Six ships have been simulated in various weather conditions at different speeds. Potential fuel savings have been estimated for a range of speed reductions in realistic weather.It is concluded that the common assumption of cubic speed-power relation can cause a significant error in the estimation of bunker consumption. Simulations in different seasons have revealed that fuel savings due to speed reduction are highly weather dependent. Therefore, a simple way to include the effect of weather in shipping transport models has been proposed.Speed reduction can lead to an increase in the number of ships to fulfill the transport demand. Therefore, the emission reduction potential of speed reduction strategy, after accounting for the additional ships, has been studied. Surprisingly, when the speed is reduced by 30%, fuel savings vary from 2% to 45% depending on ship type, size and weather conditions. Fuel savings further reduce when the auxiliary engines are considered. 相似文献
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Fuel-switching personal transportation from gasoline to electricity offers many advantages, including lower noise, zero local air pollution, and petroleum-independence. But alleviations of greenhouse gas (GHG) emissions are more nuanced, due to many factors, including the car’s battery range. We use GPS-based trip data to determine use type-specific, GHG-optimized ranges. The dataset comprises 412 cars and 384,869 individual trips in Ann Arbor, Michigan, USA. We use previously developed algorithms to determine driver types, such as using the car to commute or not. Calibrating an existing life cycle GHG model to a forecast, low-carbon grid for Ann Arbor, we find that the optimum range varies not only with the drive train architecture (plugin-hybrid versus battery-only) and charging technology (fast versus slow) but also with the driver type. Across the 108 scenarios we investigated, the range that yields lowest GHG varies from 65 km (55+ year old drivers, ultrafast charging, plugin-hybrid) to 158 km (16–34 year old drivers, overnight charging, battery-only). The optimum GHG reduction that electric cars offer – here conservatively measured versus gasoline-only hybrid cars – is fairly stable, between 29% (16–34 year old drivers, overnight charging, battery-only) and 46% (commuters, ultrafast charging, plugin-hybrid). The electrification of total distances is between 66% and 86%. However, if cars do not have the optimum range, these metrics drop substantially. We conclude that matching the range to drivers’ typical trip distances, charging technology, and drivetrain is a crucial pre-requisite for electric vehicles to achieve their highest potential to reduce GHG emissions in personal transportation. 相似文献