Characteristics of on-road NO x emissions from Euro 6 light-duty diesel vehicles using a portable emissions measurement system

Kwon, Sangil; Park, Yonghee; Park, Junhong; Kim, Jeongsoo; Choi, Kwangho; Cha, Jaehyuk

doi:10.1016/j.scitotenv.2016.10.101

Cited by 110 publications

(52 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This observation is in line with results from Ko et al [38] that found an increase of 55% NO X emissions on a test on the road performed on a diesel vehicle at 33 • C as compared to 27 • C. The increase in NO X has been explained by Kwon et al. [37] as resulting reduction of EGR rates occurring to prevent damage to EGR systems. However, no particular effect on NO X emission was found when testing diesel vehicles at 30 • C in the laboratory (still within the permitted NEDC laboratory temperature range) as compared to the standard 25 • C test.…”

Section: Discussionsupporting

confidence: 88%

See 1 more Smart Citation

Emission Factors Derived from 13 Euro 6b Light-Duty Vehicles Based on Laboratory and On-Road Measurements

et al. 2019

View full text Add to dashboard Cite

Tailpipe emissions of a pool of 13 Euro 6b light-duty vehicles (eight diesel and five gasoline-powered) were measured over an extensive experimental campaign that included laboratory (chassis dynamometer), and on-road tests (using a portable emissions measurement system). The New European Driving Cycle (NEDC) and the Worldwide harmonised Light-duty vehicles Test Cycle (WLTC) were driven in the laboratory following standard and extended testing procedures (such as low temperatures, use of auxiliaries, modified speed trace). On-road tests were conducted in real traffic conditions, within and outside the boundary conditions of the regulated European Real-Driving Emissions (RDE) test. Nitrogen oxides (NO X ), particle number (PN), carbon monoxide (CO), total hydrocarbons (HC), and carbon dioxide (CO 2 ) emission factors were developed considering the whole cycles, their sub-cycles, and the first 300 s of each test to assess the cold start effect. Despite complying with the NEDC type approval NO X limit, diesel vehicles emitted, on average, over the WLTC and the RDE 2.1 and 6.7 times more than the standard limit, respectively. Diesel vehicles equipped with only a Lean NO X trap (LNT) averaged six and two times more emissions over the WLTC and the RDE, respectively, than diesel vehicles equipped with a selective catalytic reduction (SCR) catalyst. Gasoline vehicles with direct injection (GDI) emitted eight times more NO X than those with port fuel injection (PFI) on RDE tests. Large NO X emissions on the urban section were also recorded for GDIs (122 mg/km). Diesel particle filters were mounted on all diesel vehicles, resulting in low particle number emission (~10 10 #/km) over all testing conditions including low temperature and high dynamicity. GDIs (~10 12 #/km) and PFIs (~10 11 #/km) had PN emissions that were, on average, two and one order of magnitude higher than for diesel vehicles, respectively, with significant contribution from the cold start. PFIs yielded high CO emission factors under high load operation reaching on average 2.2 g/km and 3.8 g/km on WLTC extra-high and RDE motorway, respectively. The average on-road CO 2 emissions were~33% and 41% higher than the declared CO 2 emissions at type-approval for diesel and gasoline vehicles, respectively. The use of auxiliaries (AC and lights on) over the NEDC led to an increase of~20% of CO 2 emissions for both diesel and gasoline vehicles. Results for NO X , CO and CO 2 were used to derive average on-road emission factors that are in good agreement with the emission factors proposed by the EMEP/EEA guidebook.

show abstract

Section: Discussionsupporting

confidence: 88%

“…In the laboratory, auxiliaries use did not affect NOx emissions in contrast with on-road results from [37] that reported an increase NO X EF of 68-85% associated to the use of air conditioning in diesel vehicles.…”

Section: Discussioncontrasting

confidence: 63%

Emission Factors Derived from 13 Euro 6b Light-Duty Vehicles Based on Laboratory and On-Road Measurements

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The climatic conditions between these two routes likely influenced PM emissions, with generally lower ambient temperatures and high humidity in the San Diego area due to the very close proximity to the sea. This contributed to more PM formation by the combination of PM and moisture coming from the ambient air and also generated by exhaust gas condensation (Kwon et al, 2017).…”

Section: Resultsmentioning

confidence: 99%

“…Concerns about the real-world performance of vehicles and the lack of real-world operation represented of chassis dynamometer tests are now being addressed with test protocols capable of characterizing real-world vehicle emissions. Portable emissions measurement systems (PEMS) have been widely used to measure vehicle gaseous and particulate emissions under real-world conditions (Weiss et al, 2011;Gallus et al, 2016;Kwon et al, 2017;Yang et al, 2018a). PEMS have been proved to be an important tool for emission inventories because they enable testing under a wide variety of driving conditions, including road gradients, altitude and environmental conditions variations, and strong accelerations (Zhang et al, 2019;Bishop et al, 2019;O'Driscoll et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

On-road gaseous and particulate emissions from GDI vehicles with and without gasoline particulate filters (GPFs) using portable emissions measurement systems (PEMS)

McCaffery

Zhu

et al. 2020

Science of The Total Environment

View full text Add to dashboard Cite

Editor: Karl RopkinsThis study assessed the on-road gaseous and particulate emissions from three current technology gasoline direct injection (GDI) vehicles using portable emissions measurement systems (PEMS). Two vehicles were also retrofitted with catalyzed gasoline particulate filters (GPFs). All vehicles were exercised over four routes with different topological and environmental characteristics, representing urban, rural, highway, and high-altitude driving conditions. The results showed strong reductions in particulate mass (PM), soot mass, and particle number emissions with the use of GPFs. Particle emissions were found to be highest during urban and high-altitude driving compared to highway driving. The reduction efficiency of the GPFs ranged from 44% to 99% for overall soot mass emissions. Similar efficiencies were found for particle number and PM mass emissions. In most cases, nitrogen oxide (NOx) emissions showed improvements with the catalyzed GPFs in the underfloor position with the additional catalytic volume. No significant differences were seen in carbon dioxide (CO 2 ) and carbon monoxide (CO) emissions with the vehicles retrofitted with GPFs.

show abstract

“…Only a few studies have addressed the differences found between the PEMS and laboratory grade equipment for the latest generation RDE compliant PEMS. Comparisons (validations) of PEMS on the chassis dynamometers with the bags (from the full dilution tunnel with Constant Volume Sampling [CVS]) using various driving cycles were in good agreement in most studies [10][11][12]; however, in some cases, the differences were high and exceeded the permissible tolerances [13]. However, none of these studies conducted a detailed analysis using two PEMS simultaneously, by comparing them with both the legislated method and laboratory grade analyzers at the tailpipe.…”

Section: Introductionmentioning

confidence: 82%

Comparison of Portable Emissions Measurement Systems (PEMS) with Laboratory Grade Equipment

et al. 2018

View full text Add to dashboard Cite

Real-driving emissions (RDE) testing with portable emissions measurement systems (PEMS) during the type approval and in-service conformity of light-duty vehicles was recently introduced in the European Union legislation. In this paper, three PEMS were compared with laboratory analyzers connected to the tailpipe and the dilution tunnel. The tests were conducted with two Euro 6 vehicles (one gasoline and one diesel) performing the World harmonized Light vehicles Test Cycle (WLTC) and a pre-recorded RDE cycle on a chassis dynamometer. The results showed that the differences of the PEMS gas analyzers compared to the laboratory references were typically within 2% for CO2 and 5% for NOx. The CO2 and NOx mass emissions were within 10% and 15%, respectively, with only a few exceptions. The exhaust flow rate measurements were within 10% at low speeds (urban conditions), and 5% at higher speeds. These results confirm the legislated permitted tolerances and the 2017 PEMS uncertainty estimates.

show abstract

Characteristics of on-road NO x emissions from Euro 6 light-duty diesel vehicles using a portable emissions measurement system

Cited by 110 publications

References 31 publications

Emission Factors Derived from 13 Euro 6b Light-Duty Vehicles Based on Laboratory and On-Road Measurements

Emission Factors Derived from 13 Euro 6b Light-Duty Vehicles Based on Laboratory and On-Road Measurements

On-road gaseous and particulate emissions from GDI vehicles with and without gasoline particulate filters (GPFs) using portable emissions measurement systems (PEMS)

Comparison of Portable Emissions Measurement Systems (PEMS) with Laboratory Grade Equipment

Contact Info

Product

Resources

About