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51.
This article highlights eco-driving as an available policy option to reduce climate altering GHG emissions. Recognizing the need to reduce the environmental impact of its fleet operations, the City of Calgary is a leader in developing programs and policies that aim to reduce GHG emissions and associated pollutants resulting from the use of fossil fuels. Among local action taken against climate change, the City sought to quantify CO2 emissions reductions from their municipal fleet as a result of eco-driver training, with a specific focus on engine idling. Fifteen drivers from the Development & Building Approvals Business Unit had in-vehicle monitoring technology (CarChips®) installed into their vehicles as part of a three-phase research process. The results show that gasoline and hybrid vehicles decreased average idling between 4% and 10% per vehicle per day, leading to an average emissions decrease of 1.7 kg of CO2 per vehicle per day. 相似文献
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别克轿车发动机在使用过程中若出现故障,应首先进行故障诊断并提取故障码,对有故障代码的故障可按故障代码表指示的故障部位进行检查与诊断,对无故障代码但有故障症状的故障,可按故障症状进行诊断。该发动机常见的故障症状为发动机起动困难、怠速不稳、喘振、断火或缺火、回火、爆震、功率不足及燃油经济性不良等。阐述了以上故障症状与故障诊断。 相似文献
54.
Low viscosity engine oil can improve a vehicle’s fuel economy by decreasing the friction between the engine components. Frictional
torque varies with the velocity change due to different viscosity characteristics of SAE grade 5W-20, 5W-30 and 5W-40 engine
oils. The viscosity for each of these grades was measured to outline the effect low viscosity engine oils have on engine friction,
which may lead to improved fuel economy. Engine oil seal frictional torque increases with the shaft rotational speed for all
three engine oil grades. A decrease in engine oil seal frictional torque was confirmed when low viscosity engine oil was used.
Also, the leak-free performance of the engine oil with the seal satisfied the life limit durability test criteria. Thus, low
viscosity engine oil may be used to improve fuel economy by decreasing the frictional loss of the engine oil seal while having
no negative impact on performance due to leak-free functioning. 相似文献
55.
This paper is the second invstigation on the effect of fuel stratification on flame propagation. In the previous work, the
characteristics under the no port-generated swirl condition, i.e., the conventional case was studied. In this work, the flame
development under the low swirl condition was considered. For this purpose, the initial flame development and propagation
were visualized under different axially stratified states in a modified optical single cylinder SI engine. The images were
captured by an intensified CCD camera through the quartz window mounted in the piston. Stratification was controlled by the
combination of the port swirl ratio and injection timing. These were averaged and processed to characterize the flame propagation.
The flame stability was estimated by the weighted average of flame area and luminosity. The stability was also evaluated through
the standard deviation of flame area and propagation distance and through the mean absolute deviation of the propagating direction.
The results show that the flame-flow interaction determines the direction of flame propagation and that the governing roles
of the two factors vary according to the stratified state and the location in the cylinder. In addition, the flame development
and the initial flame stability are strongly dependent on the stratified conditions, and the initial flame stability is closely
related to the engine stability and lean misfire limit. Lastly, there is no essential difference in gasoline and CNG flame
propagation characteristics. 相似文献
56.
日产GA16DE发动机怠速空气控制系统包括快怠速凸轮、怠速空气控制阀-辅助空气控制阀和怠速空气控制阀-快怠速控制装置电磁阀3部分。介绍了该机怠速空气控制系统的组成、工作原理及其各主要部件的检修。 相似文献
57.
简单介绍了发动机缸体主轴承螺栓孔的常见损伤方式,比较了镶套法,修理尺寸法和焊补法等几种修复方法的优缺点,认为采用镶套法来修复是较好的方案,并介绍了具体的修复工艺。 相似文献
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