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181.
This paper estimates the benefits, in terms of fuel and time, which continuous climb operations can save during the cruise phase of the flights, assuming maximum range operations. Based on previous works, a multiphase optimal control problem is solved by means of numerical optimization and using accurate aircraft performance data from the manufacturer. Optimal conventional trajectories (subject to current air traffic management practices and constraints) are computed and compared with ideal continuous operations only subject to aircraft performance constraints. Trip fuel and time for both concepts of operations are quantified for two aircraft types (a narrow-body and a wide-body airplane) and a representative set of different trip distances and landing masses. Results show that the continuous cruise phase can lead to fuel savings ranging from 0.5% to 2% for the Airbus A320, while for an Airbus A340 the dispersion is lower and savings lie in between 1% and 2%. Interestingly, trip time is also reduced between 1% and 5%. 相似文献
182.
The effects of fuel price increases on people’s car use have been widely discussed during the last few decades in travel behavior research. It is well recognized that fuel price has significant effects on driving distance and driving efficiency. However, most of this research assumed that these effects are invariant across individuals and weather conditions. Moreover, intrinsic variability in people’s preferences has not been given much attention due to the difficulty of collecting the necessary data. In this paper, we collected detailed travel behavior data of 276 respondents in the Netherlands, spanning a time period between one week and three months using GPS logs. These GPS data were fused with weather data, allowing us to estimate both exogenous (such as weather and fuel price) and endogenous effects (inertia and activity plans) on individual’s car use behavior. To further understand the effects of fuel price on the environment, we estimated the effects of fuel price fluctuation on CO2 emissions by car. The results show a significant degree of inertia in car use behavior in response to increased fuel prices. Weather and fuel price showed significant effects on individual’s car using behavior. Moreover, fuel price shows two-week lagged effects on individual’s travel duration by car. 相似文献
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184.
DISI甲醇发动机分层稀薄燃烧试验研究 总被引:1,自引:0,他引:1
研究了直喷火花塞点燃式(DISI)甲醇发动机1600 r/min和1200 r/min转速下整个负荷工况内分层稀薄燃烧对性能、燃烧及排放的影响。结果表明:DISI甲醇发动机在整个负荷工况内的一系列特征与柴油机和汽油机有很大不同,缸内混合气分层质量及燃油缸内空间分布对不同转速下的燃烧特性有显著影响;1200 r/min时热效率大、运转稳定,燃烧前期缸压和放热率优于1600 r/min时;大负荷时DISI甲醇发动机分层稀薄燃烧的经济性和排放性都比较好,但小负荷时的经济性和排放性较差,有待改善。 相似文献
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186.
为满足大吨位远距离运输的要求,越来越多的用户选择双油箱甚至三油箱,以提高车辆的续驶里程。但目前常用的双油箱连接效果不太理想,存在燃油渗漏甚至泄漏的现象。本文目的是提供一种新型的双油箱燃油管连接方式,实现连接的可靠性,避免车辆在使用过程中出现燃油渗漏甚至泄漏的现象,从而保证车辆行驶的可靠性,节约运输成本。 相似文献
187.
本文以AISIN公司生产的AT变速器为基础,运用汽车仿真计算方法,研究其添加新功能LOCKTOLOCK SHIFY'后,对降低燃油消耗的可能结果进行预估。在对NEDC循环的观察中发现,新功能对降低油耗有显著的作用。该计算结果为汽车厂家进一步开发和应用此项功能提供了更加充分的理论依据。 相似文献
188.
试验研究了过量空气系数和点火提前角对稀燃电控调压器式天然气发动机的燃烧以及排放的影响。试验过程对全工况的排放和动力进行了稳态优化。研究结果表明,在其他影响参数不变的情况下,随着点火提前角的减小和过量空气系数的增加,扭矩和NOX排放均降低。在匹配氧化型催化转化器后,各工况选取适当的点火提前角和过量空气系数可以满足国Ⅴ的排放标准。 相似文献
189.
Environmental considerations, concerning the negative impacts of ship exhaust gases and particles on ambient air quality, are behind the requirements of cleaner marine fuels currently applied in designated emission control areas (ECAs). We investigated the impact of a ship operating on two types of fuel on the indoor air quality onboard. Gaseous and particulate air pollutants were measured in the engine room and the accommodation sections on-board an icebreaker operating first on Heavy Fuel Oil (HFO, 1%-S), and later Marine Diesel Oil (MDO, 0.1%-S). Statistically significant decrease of SO2, NOx, PM2.5 and particle number concentration were observed when the ship was operating on MDO. Due to the higher content of alkylated PAHs in MDO compared to HFO, the concentration of PAHs increased during operation on MDO. The particulate PAHs classified as carcinogens, were similar to or lower in the MDO campaign. Chemical analysis of PM2.5 revealed that the particles consisted mainly of organic carbon and sulfate, although the fraction of metals was quite large in particles from the engine room. Principal Component Analysis of all measured parameters showed a clear difference between HFO and MDO fuel on the indoor environmental quality on-board the ship. This empirical study poses a first example on how environmental policy-making impacts not only the primary target at a global level, but also brings unexpected localized benefits at workplace level. The study emphasizes the need of further investigations on the impact of new marine fuels and technologies on the indoor air environments on board. 相似文献
190.
甲醇作为重要的车用替代燃料之一,也需要测量和计算燃料消耗量。我国已发布非醇类燃料《乘用车燃料消耗量限值》标准,试验采用甲醇汽车通过底盘测功机检测C0,CO2,HC排放量,根据碳平衡法原理得出甲醇燃料消耗量数学模型。计算燃料消耗量以及甲醇与汽油当量的体积比,并通过体积比直接将排放检测报告中的数据转化成甲醇燃料消耗量。实现了燃料经济性的定量评价。 相似文献