Using a new Mobile Atmospheric Chamber (MACh) to investigate the formation of secondary aerosols from mobile sources: The case of gasoline direct injection vehicles

Vu, Diep; Roth, Patrick; Berte, Tyler; Yang, Jiacheng; Cocker, David R.; Durbin, Thomas D.; Karavalakis, Georgios; Asa-Awuku, Akua

doi:10.1016/j.jaerosci.2019.03.009

Cited by 17 publications

(26 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All SMPS data was corrected for particle wall losses using first order wall loss kinetics, as described in detail by Cocker et al 42 Vapor wall losses have been assumed and measured to be insignificant in past chamber experiments. 37 From the volume, mass was calculated by using effective density measurements. Final mass calculations were determined from the effective density and volume calculated at the end of the irradiation experiments.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

Catalyzed Gasoline Particulate Filters Reduce Secondary Organic Aerosol Production from Gasoline Direct Injection Vehicles

Roth

Yang

Fofie

et al. 2019

Environ. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

The effects of photochemical aging on exhaust emissions from two light-duty vehicles with gasoline direct injection (GDI) engines equipped with and without catalyzed gasoline particle filters (GPFs) were investigated using a mobile environmental chamber. Both vehicles with and without the GPFs were exercised over the LA92 drive cycle using a chassis dynamometer. Diluted exhaust emissions from the entire LA92 cycle were introduced to the mobile chamber and subsequently photochemically reacted. It was found that the addition of catalyzed GPFs will significantly reduce tailpipe particulate emissions and also provide benefits in gaseous emissions, including nonmethane hydrocarbons (NMHC). Tailpipe emissions composition showed important changes with the use of GPFs by practically eliminating black carbon and increasing the fractional contribution of organic mass. Production of secondary organic aerosol (SOA) was reduced with GPF addition, but was also dependent on engine design which determined the amount of SOA precursors at the tailpipe. Our findings indicate that SOA production from GDI vehicles will be reduced with the application of catalyzed GPFs through the mitigation of reactive hydrocarbon precursors.

show abstract

Section: ■ Experimental Sectionmentioning

confidence: 99%

Catalyzed Gasoline Particulate Filters Reduce Secondary Organic Aerosol Production from Gasoline Direct Injection Vehicles

Roth

Yang

Fofie

et al. 2019

Environ. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Throughout roughly the first half of the study described here, the Mobile Air Quality Lab (MAQL) developed and operated by researchers from the University of Houston, Baylor University, and Rice University was located adjacent to the CAGE chambers at the field site. Instrumentation inside the MAQL measured trace gas concentrations and aerosol composition (Leong et al, 2017;Wallace et al, 2018). Ozone (O 3 ) was measured with a Thermo Environmental 49C analyzer.…”

Section: Experimental Procedure: Instrumentationmentioning

confidence: 99%

Captive Aerosol Growth and Evolution (CAGE) chamber system to investigate particle growth due to secondary aerosol formation

et al. 2021

View full text Add to dashboard Cite

Abstract. Environmental chambers are a commonly used tool for studying the production and processing of aerosols in the atmosphere. Most are located indoors and most are filled with air having prescribed concentrations of a small number of reactive gas species. Here we describe portable chambers that are used outdoors and filled with mostly ambient air. Each all-Teflon® 1 m3 Captive Aerosol Growth and Evolution (CAGE) chamber has a cylindrical shape that rotates along its horizontal axis. A gas-permeable membrane allows exchange of gas-phase species between the chamber and surrounding ambient air with an exchange time constant of approximately 0.5 h. The membrane is non-permeable to particles, and those that are injected into or nucleate in the chamber are exposed to the ambient-mirroring environment until being sampled or lost to the walls. The chamber and surrounding enclosure are made of materials that are highly transmitting across the solar ultraviolet and visible wavelength spectrum. Steps taken in the design and operation of the chambers to maximize particle lifetime resulted in averages of 6.0, 8.2, and 3.9 h for ∼ 0.06, ∼ 0.3, and ∼ 2.5 µm diameter particles, respectively. Two of the newly developed CAGE chamber systems were characterized using data acquired during a 2-month field study in 2016 in a forested area north of Houston, TX, USA. Estimations of measured and unmeasured gas-phase species and of secondary aerosol production in the chambers were made using a zero-dimensional model that treats chemical reactions in the chamber and the continuous exchange of gases with the surrounding air. Concentrations of NO, NO2, NOy, O3, and several organic compounds measured in the chamber were found to be in close agreement with those calculated from the model, with all having near 1.0 best fit slopes and high r2 values. The growth rates of particles in the chambers were quantified by tracking the narrow modes that resulted from injection of monodisperse particles and from occasional new particle formation bursts. Size distributions in the two chambers were measured intermittently 24 h d−1. A bimodal diel particle growth rate pattern was observed, with maxima of about 6 nm h−1 in the late morning and early evening and minima of less than 1 nm h−1 shortly before sunrise and sunset. A pattern change was observed for hourly averaged growth rates between late summer and early fall.

show abstract

“…A number of studies have demonstrated the key role gasoline vehicles are playing in the elevated SOA mass production, as a result of VOC and intermediate VOC (IVOC) emissions that are considered precursors for SOA formation [8][9][10][11]. The majority of these investigations have also reported significant exceedances of SOA mass compared to primary organic aerosol (POA) levels [12][13][14].…”

Section: Introductionmentioning

confidence: 99%

Secondary Organic and Inorganic Aerosol Formation from a GDI Vehicle under Different Driving Conditions

et al. 2022

Self Cite

View full text Add to dashboard Cite

This study investigated the primary emissions and secondary aerosol formation from a gasoline direct injection (GDI) passenger car when operated over different legislative and real-world driving cycles on a chassis dynamometer. Diluted vehicle exhaust was photooxidized in a 30 m3 environmental chamber. Results showed elevated gaseous and particulate emissions for the cold-start cycles and higher secondary organic aerosol (SOA) formation, suggesting that cold-start condition will generate higher concentrations of SOA precursors. Total secondary aerosol mass exceeded primary PM emissions and was dominated by inorganic aerosol (ammonium and nitrate) for all driving cycles. Further chamber experiments in high temperature conditions verified that more ammonium nitrate nucleates to form new particles, forming a secondary peak in particle size distribution instead of condensing to black carbon particles. The results of this study revealed that the absorption of radiation by black carbon particles can lead to changes in secondary ammonium nitrate formation. Our work indicates the potential formation of new ammonium nitrate particles during low temperature conditions favored by the tailpipe ammonia and nitrogen oxide emissions from gasoline vehicles.

show abstract

Using a new Mobile Atmospheric Chamber (MACh) to investigate the formation of secondary aerosols from mobile sources: The case of gasoline direct injection vehicles

Cited by 17 publications

References 39 publications

Catalyzed Gasoline Particulate Filters Reduce Secondary Organic Aerosol Production from Gasoline Direct Injection Vehicles

Catalyzed Gasoline Particulate Filters Reduce Secondary Organic Aerosol Production from Gasoline Direct Injection Vehicles

Captive Aerosol Growth and Evolution (CAGE) chamber system to investigate particle growth due to secondary aerosol formation

Secondary Organic and Inorganic Aerosol Formation from a GDI Vehicle under Different Driving Conditions

Contact Info

Product

Resources

About