Research On The Relationship Between Light-duty Vehicle Driving Cycle And Emission Factors On Urban Graded Roads

In recent years, with China's rapid economic growth and the continuous improvement of people's living standard, which lead to the rapid increase of motor vehicles retain mearsure, and the consequent deterioration of the urban environment. Research shows that the increase of retain measure for motor vehicles is the direct cause of increased motor vehicle pollution. Analyzing the reasons, including poor motor vehicle emission control standards and badly motor vehicle emission factor; construction of supporting facilities in the relatively backward cities, traffic management and control measures are disadvantage, the contradiction between supply and demand lead to the deterioration of driving cycles, which had increased the emission pollution. Quantitative analysis of situation of city's pollution and then make use of the pollution-control strategy is a solution to the core issue of vehicle emission pollution. City traffic and the characteristics of urban driving conditions vehicle emission factor has been the establishment and the development of the Emission Control Strategy foundation.Back in the 1940s, the Los Angeles-based oil serious air pollution-smog. California became the first country in the world to promote the implementation of the regulations controlling vehicle emissions region. Exhaust emissions in developed countries have drawn up a standard test to the United States. European and Japanese exhaust emission standards for the three most representative. The United States, Japan and European automobile emission regulations formed three vehicle emission regulations in the world.Due to the understanding of history and technical reasons, the main vehicle emissions regulations of china with reference to European standards. Beginning in 1997, it began working conditions for a typical city of light-duty vehicle, In some economically developed or have high environmental protection requirements in the city will be set up in line with the characteristics of the driving cycle. Most studies found that the only condition for the ECE-15 driving cycles with the current situation have a big difference. They have established their driving situation in the region which is necessary. City vehicles operating in the region to establish the characteristics of the actual driving conditions can provide a reliable vehicle emission control and performance optimization protection.Driving Cycle Research for quantitative analysis of the situation and the development of corresponding emission control strategy has a great significance, it can also play an important role on the traffic situation in the region and the vehicles to provide an important frame of reference for the optimization, For both these reasons launched urban graded roads the relationship between driving cycles and emission factors.Because the driving cycle is based on urban road, the test data should root in real test on urban road. The on-board emission testing system in this paper can solve this question .The total system include four parts: emission testing module ,exhaust collecting module ,engine sensors module, vehicle run condition inspecting module. The emission measure instrument is OEM-2100, which is manufactured by Clean Air Technologies Inc. of USA. The on-board emission testing system collect emission data, engine rotate speed ,intake pressure, intake temperature, vehicle operation condition parameter ect. Experiment collection data provide evidence for the establishment of driving and the analysis of emission factors. The on-board emission testing system is a feasible method for the data collection of driving cycles and emission.For the synthesis of the graded road's driving conditions, the first work is the definition of driving segments. Motor vehicles start from idling, experienced accelerating, decelerating stopped to idling is a driving segment. There are many factors which influence emissions in the actual road. We chose a greater impact on emissions of 22 parameters to define driving cycles.Through the combination of Matlab and Spss, we gained the driving parameters of expressway,main road,arterial roads and branch road four types of road conditions. The proportion of four driving conditions, the distribution of speed section and the distribution of acceleration in speed sections. It can be seen that there are widespread acceleration and deceleration and frequent low proportion of the cruise in urban graded roads. It reflects the larger impact under normal conditions, resulting in the badly flow of traffic; expressway and main roads concentrated in a relatively high rate of speed between 20 and 50km/h, while the arterial roads and branch road at a lower speed; except the interval greater acceleration, deceleration resulting increase Engine tendencies or too thin, caused by burning inadequate, increase in CO and HC emissions.Experimental use randomly selected segments and will take overall eigenvalue error control and the principle of a synthesis of various grades of road trip Traffic conditions; The results showed the urban graded roads of Changchun City driving cycles are more in line with the urban driving cycle characteristics, as follows : the average speed is low and a high proportion of Idle. The driving cycle of main road and arterial roads are more similar with Japan 10-15, speed velocity interval uniform distribution, there are more acceleration and deceleration; the driving cycle of branch roads are more similar with ECE driving cycles, reflecting the city's traffic worse situation. performance of the traffic is heavy, serious jams; highway driving conditions with CDC rapid representative of the Chinese highway driving conditions were different, the high proportion of low-speed, Idle long time without fast driving, direct access to features.Real-time emissions data on various types of roads had won three of the exhaust gas emission rates and the quality of emission factors, then do a comparison analysis; Sub-speed data points have been through all types of roads in all three points emission rate of emission factors. Research on the impact of speed on emission factors; The grading of the road and then the emission factor driving conditions at home and abroad for a comparative analysis of the emission factors, Results reflect the city's motor vehicle control at a relatively low level, it need to strengthen the control and management of the status quo, Finally, a proposal to improve traffic pollution.