On-road and laboratory evaluation of combustion aerosols—Part 2:

Kittelson, David B.; Watts, Winthrop F.; Johnson, Jennifer L.; Schauer, James J.; Lawson, Douglas R.

doi:10.1016/j.jaerosci.2005.08.008

Cited by 122 publications

(25 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Despite the wide range of overall POM concentrations among the eight vehicles, the UC drive cycle tends to result in repeatable emission patterns (Figure 1). A similar trend is reported by Kittelson et al (2006) for vehicles that were driven under the UC on chassis dynamometers but at different dilution levels. All vehicles consistently emit a higher concentration with respect to their average POM concentration during the cold-start phase (0-300 s since ignition), after which the POM concentration reaches a steady state during the hot phase (Figure 1g).…”

Section: Resultssupporting

confidence: 84%

“…Vehicle emissions are characterized by large quantities of small particles in the 30-60 nm (mobility diameter, number-weighted) range (Kittelson et al 2006) and tend to be fractal-like. As shown in Figure 2, the dominant mass-based size mode of vehicle POM is centered at D va » 90 nm with some evidence of larger particles at sizes greater than 200 nm.…”

Section: Size Distribution Of Pom In Vehicle Emissionsmentioning

confidence: 99%

“…Measurement data from Aerodyne aerosol mass spectrometers (AMS) deployed at various locations in the northern hemisphere also indicate that hydrocarbon-like organic aerosol (HOA), a surrogate for PM from primary sources such as vehicle emissions, account for 20-60% of the total OA mass in urban locations (Zhang et al 2007;Jimenez et al 2009). Other recent source apportionment studies have found significant contributions to urban PM from mobile sources, but with high variability that is accounted for by seasonal changes (Hasheminassab et al 2013), temperature (Schauer et al 2008), and differences in prevalence of vehicle type such as diesel versus gasoline (Grieshop et al 2006;Kittelson et al 2006), or driving conditions such as traffic intensity Sun et al 2012).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Organic PM Emissions from Vehicles: Composition, O/C Ratio, and Dependence on PM Concentration

Collier

Zhou

Kuwayama

et al. 2015

Aerosol Science and Technology

View full text Add to dashboard Cite

A suite of real-time instruments was used to sample vehicle emissions at the California Air Resources Board Haagen-Smit facility. Eight on-road, spark-ignition gasoline and three alternative vehicles were tested on a chassis dynamometer and the emissions were diluted to atmospherically relevant concentrations (0.5-30 mg/m 3 ). An Aerodyne high resolution time-of-flight aerosol mass spectrometer (HR-ToF-MS) characterized the real-time behavior of the nonrefractory organic and inorganic particulate matter (PM) in vehicle emissions. It was found that the emission of particulate organic matter (POM) was strongly affected by engine temperature and engine load and that the emission concentrations could vary significantly by vehicle. Despite the small sample size, consistent trends in chemical characteristics were observed. The composition of vehicle POM was found to be related to overall PM mass concentration where the oxygen-to-carbon (O/C) ratio tended to increase at lower concentration and had an average value of 0.057 § 0.047, with a range from 0.022 to 0.15. The corresponding fraction of particle-phase CO 2 C , or f 44 , ranged from 1.1% to 8.6% (average D 2.1%) and exhibited a linear variation with O/ C. The average mass spectrum from all vehicles tested was also compared to those of hydrocarbon-like organic aerosol (HOA) observed in ambient air and the agreement is very high. The results of these tests offer the vehicle emissions community a first glimpse at the real-time chemical composition and variation of vehicle PM emissions for a variety of conditions and vehicle types at atmospherically relevant conditions and without chemical interferences from other primary or secondary aerosol sources.

show abstract

Section: Resultssupporting

confidence: 84%

Section: Size Distribution Of Pom In Vehicle Emissionsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Organic PM Emissions from Vehicles: Composition, O/C Ratio, and Dependence on PM Concentration

Collier

Zhou

Kuwayama

et al. 2015

Aerosol Science and Technology

View full text Add to dashboard Cite

show abstract

“…Kittelson et al [39] investigating both on-road and laboratory aerosol emission from four, heavy-duty diesel truck It is worth mentioning that a bimodal shape of the particle size distribution, similar to the one reported herein, has been already observed by measuring ultrafine particles from a gas-turbine burning several hydrocarbon and bio-derived liquid fuels [37]. In addition, the presence of a bimodal particle size distribution has been observed under diesel [39] and gasoline spark ignition engine operations [40], although for the gasoline engine particle number emission above the background level was mainly reported to occur during specific combustion regimes such as during acceleration, high-speed cruise, and during cold-cold starts [39].…”

Section: Particle Concentrations and Number Size Distributionssupporting

confidence: 84%

Pollutant Formation during the Occurrence of Flame Instabilities under Very-Lean Combustion Conditions in a Liquid-Fuel Burner

et al. 2017

View full text Add to dashboard Cite

Recent advances in gas turbine combustor design are aimed at achieving low exhaust emissions, hence modern aircraft jet engines are designed with lean-burn combustion systems. In the present work, we report an experimental study on lean combustion in a liquid fuel burner, operated under a non-premixed (single point injection) regime that mimics the combustion in a modern aircraft engine. The flame behavior was investigated in proximity of the blow-out limit by an intensified high rate Charge-Coupled Device (CCD) camera equipped with different optical filters to selectively record single species chemiluminescence emissions (e.g., OH*, CH*). Analogous filters were also used in combination with photomultiplier (PMT) tubes. Furthermore this work investigates well-mixed lean low NO x combustion where mixing is good and generation of solid carbon particulate emissions should be very low. An analysis of pollutants such as fine particles and gaseous emissions was also performed. Particle number concentrations and size distributions were measured at the exhaust of the combustion chamber by two different particle size measuring instruments: a scanning mobility particle sizer (SMPS) and an Electrical Low Pressure Impactor (ELPI). NO x concentration measurements were performed by using a cross-flow modulation chemiluminescence detection system; CO concentration emissions were acquired with a Cross-flow modulation Non-dispersive infrared (NDIR) absorption method. All the measurements were completed by diagnostics of the fundamental combustor parameters. The results herein presented show that at very-lean conditions the emissions of both particulate matter and CO was found to increase most likely due to the occurrence of flame instabilities while the NO x were observed to reduce.

show abstract

“…This technique is being used by several groups to obtain a representative image of particle emission evolution in the wake of the vehicle. [42][43][44] This technique has the advantage of isolating particle emissions from a single vehicle and measuring concentrations without interference from the sampling system. On the counterside, chasing experiments lead to emission characterization under very specific ambient (weather) and driving conditions.…”

Section: Discussionmentioning

confidence: 99%

The Potential of a Partial-Flow Constant Dilution Ratio Sampling System as a Candidate for Vehicle Exhaust Aerosol Measurements Leonidas Ntziachristos

Ntziachristos

Samaras

2010

Journal of the Air & Waste Management Association

View full text Add to dashboard Cite

This paper presents the measurement of airborne particle properties with use of a dedicated sampling protocol and a measurement setup directly installed in the exhaust line of vehicles and engines. The sampling system dilutes a small part of the exhaust directly at the tailpipe without the need of exhaust gas transfer lines that may lead to sampling artifacts. Dilution takes place in two steps with a primary dilution ratio universally set at a value of 12.5:1 for all vehicles and engines tested, and subsequent dilution steps reducing particle concentration within the measuring range of the instruments used. Dilution air temperature and residence time were set at 32°C and 2.5 sec respectively, to allow repeatable measurement of nucleation-mode particles. The paper summarizes the specifications of the system, evaluates its performance in comparison to real-world dilution (chasing experiments), and presents the repeatability and reproducibility of measurements performed in different laboratories. In general, after taking precautions for the setup and condition of instruments, both measurement quality indices reached levels similar to the measurement of particulate matter (PM) mass. Application of the system, using the same protocol, to measure many light-duty vehicles and engines is finally demonstrated, providing useful conclusions for the emission performance of different sized engines. The study concludes that the use of partial-flow sampling systems may offer advantages for the measurement of particle emissions from low-emission engines compared with constant volume sampling facilities, including lower cost of purchase and operation, versatility, lack of artifacts, and possibilities for standardization in different environments.

show abstract

On-road and laboratory evaluation of combustion aerosols—Part 2:

Cited by 122 publications

References 23 publications

Organic PM Emissions from Vehicles: Composition, O/C Ratio, and Dependence on PM Concentration

Organic PM Emissions from Vehicles: Composition, O/C Ratio, and Dependence on PM Concentration

Pollutant Formation during the Occurrence of Flame Instabilities under Very-Lean Combustion Conditions in a Liquid-Fuel Burner

The Potential of a Partial-Flow Constant Dilution Ratio Sampling System as a Candidate for Vehicle Exhaust Aerosol Measurements Leonidas Ntziachristos

Contact Info

Product

Resources

About