Emissions of Light-Duty Vehicles with Respect to Cruising Speed under Real-World Driving Conditions

Vehicle emissions standards and regulations remain weak in high-altitude regions. In this study, vehicle emissions from both the New European Driving Cycle and the Worldwide harmonized Light-duty driving Test Cycle were analyzed by employing on-road test data collected from typical roads in a high-altitude city. On-road measurements were conducted on five light-duty vehicles using a portable emissions measurement system. The certification cycle parameters were synthesized from real-world driving data using the vehicle specific power methodology. The analysis revealed that under real-world driving conditions, all emissions were generally higher than the estimated values for both the New European Driving Cycle and Worldwide harmonized Light-duty driving Test Cycle. Concerning emissions standards, more CO, NOx, and hydrocarbons were emitted by China 3 vehicles than by China 4 vehicles, whereas the CO2 emissions exhibited interesting trends with vehicle displacement and emissions standards. These results have potential implications for policymakers in regard to vehicle emissions management and control strategies aimed at emissions reduction, fleet inspection, and maintenance programs.

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Measurement and Evaluation of Real-World Speed and Acceleration Activity Envelopes for Light-Duty Vehicles

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/2503-14 ◽

2015 ◽

Vol 2503 (1) ◽

pp. 128-136 ◽

Cited By ~ 8

Author(s):

Bin Liu ◽

H. Christopher Frey

Keyword(s):

Real World ◽

Test Procedure ◽

Accurate Estimation ◽

Vehicle Type ◽

Light Duty ◽

Road Grade ◽

Light Duty Vehicle ◽

Curb Weight ◽

Vehicle Activity ◽

Light Duty Vehicles

Accurate estimation of vehicle activity is critically important for the accurate estimation of emissions. To provide a benchmark for estimation of vehicle speed trajectories such as those from traffic simulation models, this paper demonstrates a method for quantifying light-duty vehicle activity envelopes based on real-world activity data for 100 light-duty vehicles, including conventional passenger cars, passenger trucks, and hybrid electric vehicles. The vehicle activity envelope was quanti-fied in the 95% frequency range of acceleration for each of 15 speed bins with intervals of 5 mph and a speed bin for greater than 75 mph. Potential factors affecting the activity envelope were evaluated; these factors included vehicle type, transmission type, road grade, engine displacement, engine horsepower, curb weight, and ratio of horsepower to curb weight. The activity envelope was wider for speeds ranging from 5 to 20 mph and narrowed as speed increased. The latter was consistent with a constraint on maximum achievable engine power demand. The envelope was weakly sensitive to factors such as type of vehicle, type of transmission, road grade, and engine horsepower. The effect of road grade on cycle average emissions rates was evaluated for selected real-word cycles. The measured activity envelope was compared with those of dynamometer driving cycles, such as the federal test procedure, highway fuel economy test, SC03, and US06 cycles. The effect of intervehicle variability on the activity envelope was minor; this factor implied that the envelope could be quantified based on a smaller vehicle sample than used for this study.

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Emissions of Light Duty Vehicle Tested under Urban and Extraurban Real-World Driving Conditions with Diesel, Animal Fat Biodiesel and GTL fuels

10.4271/2013-24-0176 ◽

2013 ◽

Cited By ~ 7

Author(s):

Octavio Armas ◽

Reyes Garcia-Contreras ◽

Angel Ramos

Keyword(s):

Real World ◽

Animal Fat ◽

Light Duty ◽

Light Duty Vehicle ◽

Driving Conditions

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Greenhouse Gas Emissions from Light Duty Vehicles Under a Variety of Driving Conditions

2006 IEEE EIC Climate Change Conference ◽

10.1109/eicccc.2006.277273 ◽

2006 ◽

Cited By ~ 5

Author(s):

Lisa Graham

Keyword(s):

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Gas Emissions ◽

Light Duty ◽

Driving Conditions ◽

Light Duty Vehicles

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Speed- and Facility-Specific Emission Estimates for On-Road Light-Duty Vehicles on the Basis of Real-World Speed Profiles

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198106198700114 ◽

2006 ◽

Vol 1987 (1) ◽

pp. 128-137 ◽

Cited By ~ 22

Author(s):

H. Christopher Frey ◽

Nagui M. Rouphail ◽

Haibo Zhai

Keyword(s):

Real World ◽

Light Duty ◽

Light Duty Vehicles

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Analysis of Driving Cycles for Emission Test of Light-Duty Vehicles in China

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.616-618.1154 ◽

2012 ◽

Vol 616-618 ◽

pp. 1154-1160

Author(s):

Jin Lin Xue

Keyword(s):

Real World ◽

Gasoline Engine ◽

The Real ◽

Driving Behaviors ◽

Traffic Conditions ◽

Driving Cycles ◽

Driving Pattern ◽

Light Duty ◽

Light Duty Vehicles ◽

The Impact

The driving cycles employed to measure the emissions from automotive vehicles should adequately represent the real-world driving pattern of the vehicle to provide the most realistic estimation of emissions levels. The driving cycles used for light-duty gasoline engine vehicles in China were reviewed in this paper firstly. Then the impact of various factors, such as driving behaviors, driving conditions, road conditions, traffic conditions, on real-world emission levels were analyzed. Finally, the shortages of the existing driving cycles were pointed out. It can be concluded that the emissions levels from automotive vehicles are underestimated because of the characteristics of the existing drive cycles, so it is urgent to research and develop new driving cycles to fit the situation of China.

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Estimation of Real-World Fuel Consumption Rate of Light-Duty Vehicles Based on the Records Reported by Vehicle Owners

Energies ◽

10.3390/en14237915 ◽

2021 ◽

Vol 14 (23) ◽

pp. 7915

Author(s):

Isabella Yunfei Zeng ◽

Shiqi Tan ◽

Jianliang Xiong ◽

Xuesong Ding ◽

Yawen Li ◽

...

Keyword(s):

Fuel Consumption ◽

Real World ◽

Consumption Rate ◽

The Real ◽

Fuel Consumption Rate ◽

Light Gradient ◽

Light Duty ◽

Light Duty Vehicle ◽

Light Duty Vehicles ◽

Engine Power

Private vehicle travel is the most basic mode of transportation, so that an effective way to control the real-world fuel consumption rate of light-duty vehicles plays a vital role in promoting sustainable economic growth as well as achieving a green low-carbon society. Therefore, the factors impacting individual carbon emissions must be elucidated. This study builds five different models to estimate the real-world fuel consumption rate of light-duty vehicles in China. The results reveal that the light gradient boosting machine (LightGBM) model performs better than the linear regression, naïve Bayes regression, neural network regression, and decision tree regression models, with a mean absolute error of 0.911 L/100 km, a mean absolute percentage error of 10.4%, a mean square error of 1.536, and an R-squared (R2) value of 0.642. This study also assesses a large pool of potential factors affecting real-world fuel consumption, from which the three most important factors are extracted, namely, reference fuel-consumption-rate value, engine power, and light-duty vehicle brand. Furthermore, a comparative analysis reveals that the vehicle factors with the greatest impact are the vehicle brand, engine power, and engine displacement. The average air pressure, average temperature, and sunshine time are the three most important climate factors.

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