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用传统方法分析行驶循环燃油经济性时,运动学模型无法采集到增压空气处理系统中的瞬态差异。建立一维动力学性能仿真模型预测行驶循环燃油经济性,它包含了发动机和车辆模型的所有瞬态元素。令人感兴趣的瞬态技术是机械增压,其优点在于可改善增压响应,缩短达到最大扭矩的时间。评价了机械增压器离合器带来的好处。当前的美国6~8级商用车市场只采用涡轮增压柴油机。根据对车辆销售和二手卡车市场进行调查的结果,选择了3辆车和基本型动力总成。行驶循环的燃油经济性是仿真工作的主要输出。所有动力总成都符合美国环保署2010年排放法规要求。同时包括2种降低氮氧化物的方法:(1)仅采用高比例废气再循环,(2)采用低比例废气再循环+选择性催化还原装置的后处理系统。在工作过程中开发了2种采用GT-Suite的新型建模方法。高水准的动力学模型对中央处理器性能强度的要求更高,但提供的输出不能用更快运行的稳态或运动学模型加以解释。机械增压配置对增压响应的改进体现在车辆性能的提高,而又不增加额定的功率/扭矩比。与基本型涡轮增压动力总成相比,机械增压应用不同水平的降速,既可提高车辆性能或燃油经济性,也可使两者同时得以改进。还评价了机械增压器的尺寸和布置方式(在串联增压配置中放在压气机之前或之后),以及废气再循环回路的布置方式。在3辆车的应用中,均实现了燃油经济性的改善。
When analyzing the driving cycle fuel economy with the traditional method, the kinematic model can not capture the transient differences in the pressurized air handling system. A one-dimensional kinetic performance simulation model is built to predict the driving cycle fuel economy, which includes all the transient elements of the engine and vehicle models. The transient technology of interest is supercharging, which has the advantage of improving boost response and shortening the time to maximum torque. Evaluated the benefits of supercharger clutches. The current US 6-8 commercial vehicle market only uses turbocharged diesel engines. Based on the results of surveys of the vehicle sales and the used truck market, three cars and the basic powertrain were selected. The fuel economy of the driving cycle is the main output of the simulation. All powertrain meets US EPA’s 2010 emissions regulations. Also included are two ways to reduce nitrogen oxides: (1) use only high proportions of exhaust gas recirculation, and (2) use aftertreatment systems with a low ratio of exhaust gas recirculation + selective catalytic reduction units. Two new modeling methods using GT-Suite were developed during the course of their work. High-level kinetic models have higher CPU performance requirements, but the output provided can not be explained by steady-state or kinematic models that operate faster. The boost response of the supercharged configuration is reflected in improved vehicle performance without increasing the rated power / torque ratio. Compared with the basic turbocharged powertrain, the application of different levels of mechanical booster deceleration, either to improve vehicle performance or fuel economy, but also both can be improved. The size and arrangement of the supercharger (before or after the compressor in a tandem supercharging configuration) and the arrangement of the exhaust gas recirculation circuit were also evaluated. In 3 car applications, have achieved a fuel economy improvement.