scholarly journals Comparison of fuel consumption and exhaust emissions in WLTP and NEDC procedures

2019 ◽  
Vol 179 (4) ◽  
pp. 186-191
Author(s):  
Grzegorz KOSZAŁKA ◽  
Andrzej SZCZOTKA ◽  
Andrzej SUCHECKI

Fuel consumption achieved in the New European Driving Cycle (NEDC) could be 50% lower than the fuel consumption in real driving conditions and in the case of emissions of regulated toxic compounds the differences could even be much greater. In order to bring the results achieved in official tests closer to real life figures, the European Commission introduced in 2017 the Worldwide Harmonized Light Vehicles Test Procedure (WLTP), which replaced the NEDC. In this article the results of fuel consumption and exhaust emissions for 3 cars fitted with engines of the same displacement but with direct and indirect gasoline injection, determined according to the NEDC and WLTC were presented. The results show that the effect of driving cycle on the fuel consumption is equivocal – for one car, fuel consumption was higher in the WLTC; for the other one in the NEDC; and for the third one, fuel consumption achieved in both driving cycles was practically the same. Emissions of regulated exhaust compounds, except for THC, obtained in the WLTC were higher than in the NEDC driving cycle.

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3064 ◽  
Author(s):  
José Huertas ◽  
Michael Giraldo ◽  
Luis Quirama ◽  
Jenny Díaz

Type-approval driving cycles currently available, such as the Federal Test Procedure (FTP) and the Worldwide harmonized Light vehicles Test Cycle (WLTC), cannot be used to estimate real fuel consumption nor emissions from vehicles in a region of interest because they do not describe its local driving pattern. We defined a driving cycle (DC) as the time series of speeds that when reproduced by a vehicle, the resulting fuel consumption and emissions are similar to the average fuel consumption and emissions of all vehicles of the same technology driven in that region. We also declared that the driving pattern can be described by a set of characteristic parameters (CPs) such as mean speed, positive kinetic energy and percentage of idling time. Then, we proposed a method to construct those local DC that use fuel consumption as criterion. We hypothesized that by using this criterion, the resulting DC describes, implicitly, the driving pattern in that region. Aiming to demonstrate this hypothesis, we monitored the location, speed, altitude, and fuel consumption of a fleet of 15 vehicles of similar technology, during 8 months of normal operation, in four regions with diverse topography, traveling on roads with diverse level of service. In every region, we considered 1000 instances of samples made of m trips, where m varied from 4 to 40. We found that the CPs of the local driving cycle constructed using the fuel-based method exhibit small relative differences (<15%) with respect to the CPs that describe the driving patterns in that region. This result demonstrates the hypothesis that using the fuel based method the resulting local DC exhibits CPs similar to the CPs that describe the driving pattern of the region under study.


2021 ◽  
Vol 1 (50) ◽  
pp. 67-80
Author(s):  
JAWORSKI A ◽  
◽  
JAREMCIO M ◽  
LEJDA K ◽  
MĄDZIEL M ◽  
...  

The manufacturing process for new passenger vehicles is based not only on their design and manufacture, but also on validation and testing, especially in the area of exhaust emissions. The car manufacturer is obliged to approve the type of each new model in accordance with the regulations. The regulation associated with the relevant directive includes a number of requirements, including the emissions of pollutants in the exhaust gas, which are imposed on newly manufactured vehicles. Along with the development of the automotive industry, more and more attention has been paid to the pollution that forms in the internal combustion engines of vehicles. The European Union has introduced standards known as “EURO” to define emission limits for the main pollutants in exhaust gases. The tests are carried out for all passenger cars in the same way: on a dynamometer, in a climatic chamber (with the possibility of temperature adjustment) and in accordance with a certain driving cycle. Road tests are designed to check fuel consumption and exhaust emissions. In September 2017, a new procedure was introduced called the World Harmonized Light Vehicle Test Procedure (WLTP), which includes several driving cycles called WLTC. The introduction of the new test was driven by the very dynamic development in the automotive industry of hybrid and electric vehicles. The previous NEDC test did not take into account several important parameters such as motor power or drive type. Due to the different specifics of road traffic in the United States, their own road tests were developed, in contrast to European ones. Tests are conducted in accordance with FTP-75 (Federal Testing Procedure). The test parameters take into account driving stability and engine operating conditions, on which the values of pollutant emissions in the exhaust gases depend. Due to the difference in laboratory driving cycles, according to traffic conditions, the values of pollutant emissions in the exhaust gases during road tests differ from those provided by the manufacturers. The article compares the characteristic test parameters according to WLTC, NEDC, American FTP-75 cycles (with additions SC03 and US06) and own road driving cycle in the Rzeszow region. Based on the analysis carried out, it was established that laboratory tests will never 100% reflect those driving conditions and driving on the road. However, the WLTC test has the advantage of being more realistic. Its high average ride speeds, longer stops, long distance traveled and higher top speed are more realistic than the NEDC test. KEY WORDS: VEHICLE TESTING, EFFECTIVE Emissions, WORLD HARMONIZED PASSENGER VEHICLE TEST PROCEDURE, NEW EUROPEAN DRIVING CYCLE, FEDERAL TESTING PROCEDURE.


Author(s):  
Andrzej Kuranc ◽  
Jacek Caban ◽  
Branislav Šarkan ◽  
Agnieszka Dudziak ◽  
Monika Stoma

Road transport have significant impact on regional economic and social development, but one can also point out a number of its disadvantages, which include environmental pollution. The paper presents measurements of fumes exhaust emissions of a passenger car with a significant operational mileage. The tests were carried out in a laboratory on a chassis roller dynamometer using various driving cycles. To determine the exhaust emissions, data on the mass of air flowing through the intake manifold was used, among others. The work also describes an example of own driving cycle developed based on urban driving in Lublin, Poland.


2018 ◽  
Vol 7 (4.19) ◽  
pp. 939
Author(s):  
Haider S. Najem ◽  
Qahtan A. Jawad ◽  
Abdulbaki K. Ali ◽  
Basil S. Munahi

In this paper, a statistical method is employed to develop a driving cycle for Basrah city and to find out the factor score and the Euclidean distance analysis by the Statistical Package for the Social Sciences (SPSS). A simple electronic system is built to construct the driving cycle, the system considered a microcontroller and a GPS sensor connected to a PC through a simple C++ code. The development of the proposed driving cycle represents the first model driving cycle in the city of Basra. The advisor software package is used to investigate the economic performance of the internal combustion engine based on HC, CO, and NOx exhaust emissions. It was found that the obtained driving cycle is significantly different than the other driving cycles in terms of exhaust emissions and fuel consumption and within the expected range of emissions. The developed driving cycle model obtained is a representative delicate estimation of the exhaust emissions and fuel consumption, and will be utilized for future work to obtain a good performance of the hybrid electric vehicles.  


Author(s):  
Hanna Sara ◽  
David Chalet ◽  
Mickaël Cormerais

Exhaust gas heat recovery is one of the interesting thermal management strategies that aim to improve the cold start of the engine and thus reduce its fuel consumption. In this work, an overview of the heat exchanger used as well as the experimental setup and the different tests will be presented first. Then numerical simulations were run to assess and valorize the exhaust gas heat recovery strategy. The application was divided into three parts: an indirect heating of the oil with the coolant as a medium fluid, a direct heating of the oil, and direct heating of the oil and the coolant. Different ideas were tested over five different driving cycles: New European driving cycle (NEDC), worldwide harmonized light duty driving test cycle (WLTC), common Artemis driving cycle (CADC) (urban and highway), and one in-house developed cycle. The simulations were performed over two ambient temperatures. Different configurations were proposed to control the engine's lubricant maximum temperature. Results concerning the temperature profiles as well as the assessment of fuel consumption were stated for each case.


Author(s):  
Hanna Sara ◽  
David Chalet ◽  
Mickaël Cormerais ◽  
Jean-François Hetet

Since the main interest worldwide of green environment companies is to reduce pollutant emissions, the automotive industry is aiming to improve engine efficiency in order to reduce fuel consumption. Recently, studies have been shifted from upgrading the engine to the auxiliary systems attached to it. Thermal management is one of the successful fields that has shown promise in minimizing fuel consumption and reducing pollutant emissions. Throughout this work, a four-cylinder turbocharged diesel engine model was developed on GT-Power. Also, a thermal code has been developed in parallel on GT-Suite, in which the different parts of the coolant and lubricant circuits were modeled and calibrated to have the best agreement with the temperature profile of the two fluids in the system. Once the model was verified, hot coolant storage, a thermal management strategy, was applied to the system to assess the fuel consumption gain. The storage tank was located downstream the thermostat and upstream the radiator with three valves to control the coolant flow. The place was chosen to avoid negative impact on the cold start-up of the engine when the tank is at the ambient temperature. This strategy was applied on different driving cycles such as the NEDC, WLTC, CADC (urban and highway), and an in-house developed driving cycle. The ambient temperature was varied between −7°C to represent the coldest winter and 20°C. The results of this study summarize the ability of the hot coolant storage strategy in reducing the fuel consumption, and show the best driving cycle that needs to be applied on along with the influence of the different ambient temperatures.


2017 ◽  
Author(s):  
Pawel Fuc ◽  
Piotr Lijewski ◽  
Przemyslaw Kurczewski ◽  
Andrzej Ziolkowski ◽  
Michal Dobrzynski

The paper presents an analysis of gaseous exhaust emissions and fuel consumption obtained from two forklifts based on the measurements performed under actual driving conditions. The first of the investigated objects was fitted with a diesel engine and the second with a spark ignition engine fueled with LPG. In order to carry out the research, the authors developed a proprietary methodology because the VDI 2198 test procedure (developed by VDI - Association of German Engineers) for the determination of forklift energy consumption, did not fully reflect the actual conditions of operation of these vehicles. The VDI procedure only determines the energy consumption according to predetermined sequences (collecting load, load transport, load-dropping) performed only in indoor areas. The authors developed a test route composed of similar sequences i.e. collecting load, load transport, load-dropping and driving without a load. The measurements were carried out in a warehouse and outdoors, which better reflected the actual forklift driving conditions. During the trials, the exhaust emissions were measured (Semtech - Portable Emission Measurement System) along with the driving parameters such as speed, acceleration and distance covered. Based on the obtained parameters, on-road exhaust emissions and fuel consumption were obtained. The obtained data allowed a comparison of the measurement conditions and the type of fuel used for the forklifts. Both tested vehicles were loaded with identical type of load of the same weight.


Author(s):  
Jeff Howell ◽  
David Forbes ◽  
Martin Passmore

The aerodynamic drag characteristics of a passenger car have, typically, been defined by a single parameter: the drag coefficient at a yaw angle of 0°. Although this has been acceptable in the past, it does not provide an accurate measure of the effect of aerodynamic drag on fuel consumption because the important influence of the wind has been excluded. The result of using drag coefficients at a yaw angle of 0° produces an underprediction of the aerodynamic component of fuel consumption that does not reflect the on-road conditions. An alternative measure of the aerodynamic drag should take into account the effect of non-zero yaw angles, and a variant of wind-averaged drag is suggested as the best option. A wind-averaged drag coefficient is usually derived for a particular vehicle speed using a representative wind speed distribution. In the particular case where the road speed distribution is specified, such as for a driving cycle to determine fuel economy, a relevant drag coefficient can be derived by using a weighted road speed. An effective drag coefficient is determined with this approach for a range of cars using the proposed test cycle for the Worldwide Harmonised Light Vehicle Test Procedure, WLTP. The wind input acting on the car has been updated for this paper using recent meteorological data and an understanding of the effect of a shear flow on the drag loading obtained from a computational fluid dynamics study. In order to determine the different mean wind velocities acting on the car, a terrain-related wind profile has also been applied to the various phases of the driving cycle. An overall drag coefficient is derived from the work done over the full cycle. This cycle-averaged drag coefficient is shown to be significantly higher than the nominal drag coefficient at a yaw angle of 0°.


2013 ◽  
Vol 390 ◽  
pp. 343-349 ◽  
Author(s):  
Jerzy Merkisz ◽  
Pawel Fuc ◽  
Piotr Lijewski ◽  
Andrzej Ziolkowski

The paper describes the influence of the start-stop system on the exhaust emissions and fuel consumption. The tests were performed for two vehicles. The first one was a vehicle designed specifically to operate in city conditions. It was fitted with a gasoline engine of the displacement of 0.9 dm3 and maximum power output of 63.7 kW. The other vehicle was an SUV (Sports Utility Vehicle) fitted with a diesel engine of the displacement of 3.0 dm3. The measurements of the exhaust emission were carried out on the same route under actual traffic conditions. For the tests a portable exhaust emissions analyzer from the PEMS group SEMTECH DS was used (PEMS Portable Emissions Measurement System).


2016 ◽  
Vol 822 ◽  
pp. 331-340
Author(s):  
Dan Mihai Dogariu ◽  
Anghel Chiru ◽  
Cristian Ioan Leahu

The electrification of the powertrain is one of the best solutions in the quest for obtaining emissions within the even more narrow limits imposed by legislation, with no penalty to the dynamic performances of the vehicle. This article describes a study regarding the possibilities of hybridization of a road vehicle. Based on real life situations, the custom driving cycles have been defined by means of GPS tracking. These driving patterns were further used in a simulation environment to test various configurations of classical and hybrid powertrains. The performances of the vehicle before and after hybridization were compared pursuing the change in emissions and fuel consumption.


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