Measuring diesel soot with a scanning mobility particle sizer and an electrical low-pressure impactor: Performance assessment with a model for fractal-like agglomerates

C. Van Gulijk, J. C.M. Marijnissen, M. Makkee, J. A. Moulijn, A. Schmidt-Ott

Research output: Contribution to journalArticle

122 Citations (Scopus)

Abstract

The scanning mobility particle sizer (SMPS) and the electrical low-pressure impactor (ELPI) are frequently used to measure particle size distributions of combustion aerosols. The instruments are especially popular for diesel exhaust measurements since the emission of "particulate matter" is restricted by legislation. A problem is that the interpretation of the results that these instruments give is not straightforward: fractal-like diesel soot agglomerates in the exhaust have a complex interaction with their carrier gas. This paper focuses on this complex interaction in order to assess its effect on the instruments' output. A theoretical model for the aerodynamic behavior of fractal-like agglomerates is used as a tool to assess the performance of the ELPI and the SMPS for the measurement of diesel soot particles. The model couples the aerodynamic diameter and the mobility diameter for fractal-like soot agglomerates. Visual analysis with scanning electron microscopy (SEM) aids model development and instrument performance assessment. It is concluded that the performance of both instruments is affected by the fractal-like structure of diesel soot. The ELPI, if it is set to measure the aerodynamic diameter, gives an underestimation of the apparent size of particles due to their fractal-like structure. As a result, the number of particles is overestimated. The model presented in this paper helps interpretation of the ELPIs response. The SMPS is affected by multiple charging of soot agglomerates, larger than 1000 nm, which are abundantly present in diesel exhaust gas and are not removed by the impaction stage at the input due to their small effective density. The diesel engine in this paper emits many of such particles. Multiple charging leads to an underestimation of the size of the agglomerates and hampers size classification in the instrument.

LanguageEnglish
Pages633-655
Number of pages23
JournalJournal of Aerosol Science
Volume35
Issue number5
Early online date21 Jan 2004
DOIs
Publication statusPublished - May 2004
Externally publishedYes

Fingerprint

Soot
performance assessment
soot
Fractals
diesel
low pressure
Scanning
Vehicle Emissions
Aerodynamics
aerodynamics
Particulate Matter
visual analysis
Exhaust gases
Aerosols
Particle size analysis
diesel engine
Diesel engines
particle
measuring
impactor

Cite this

@article{10c44b2684c74412bf61161e33c50ffb,
title = "Measuring diesel soot with a scanning mobility particle sizer and an electrical low-pressure impactor: Performance assessment with a model for fractal-like agglomerates",
abstract = "The scanning mobility particle sizer (SMPS) and the electrical low-pressure impactor (ELPI) are frequently used to measure particle size distributions of combustion aerosols. The instruments are especially popular for diesel exhaust measurements since the emission of {"}particulate matter{"} is restricted by legislation. A problem is that the interpretation of the results that these instruments give is not straightforward: fractal-like diesel soot agglomerates in the exhaust have a complex interaction with their carrier gas. This paper focuses on this complex interaction in order to assess its effect on the instruments' output. A theoretical model for the aerodynamic behavior of fractal-like agglomerates is used as a tool to assess the performance of the ELPI and the SMPS for the measurement of diesel soot particles. The model couples the aerodynamic diameter and the mobility diameter for fractal-like soot agglomerates. Visual analysis with scanning electron microscopy (SEM) aids model development and instrument performance assessment. It is concluded that the performance of both instruments is affected by the fractal-like structure of diesel soot. The ELPI, if it is set to measure the aerodynamic diameter, gives an underestimation of the apparent size of particles due to their fractal-like structure. As a result, the number of particles is overestimated. The model presented in this paper helps interpretation of the ELPIs response. The SMPS is affected by multiple charging of soot agglomerates, larger than 1000 nm, which are abundantly present in diesel exhaust gas and are not removed by the impaction stage at the input due to their small effective density. The diesel engine in this paper emits many of such particles. Multiple charging leads to an underestimation of the size of the agglomerates and hampers size classification in the instrument.",
keywords = "Agglomerates, Diesel soot, ELPI, Fractal-like, Instrument evaluation, SMPS",
author = "{Van Gulijk}, C. and Marijnissen, {J. C.M.} and M. Makkee and Moulijn, {J. A.} and A. Schmidt-Ott",
year = "2004",
month = "5",
doi = "10.1016/j.jaerosci.2003.11.004",
language = "English",
volume = "35",
pages = "633--655",
journal = "Journal of Aerosol Science",
issn = "0021-8502",
publisher = "Elsevier Limited",
number = "5",

}

Measuring diesel soot with a scanning mobility particle sizer and an electrical low-pressure impactor : Performance assessment with a model for fractal-like agglomerates. / Van Gulijk, C.; Marijnissen, J. C.M.; Makkee, M.; Moulijn, J. A.; Schmidt-Ott, A.

In: Journal of Aerosol Science, Vol. 35, No. 5, 05.2004, p. 633-655.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Measuring diesel soot with a scanning mobility particle sizer and an electrical low-pressure impactor

T2 - Journal of Aerosol Science

AU - Van Gulijk, C.

AU - Marijnissen, J. C.M.

AU - Makkee, M.

AU - Moulijn, J. A.

AU - Schmidt-Ott, A.

PY - 2004/5

Y1 - 2004/5

N2 - The scanning mobility particle sizer (SMPS) and the electrical low-pressure impactor (ELPI) are frequently used to measure particle size distributions of combustion aerosols. The instruments are especially popular for diesel exhaust measurements since the emission of "particulate matter" is restricted by legislation. A problem is that the interpretation of the results that these instruments give is not straightforward: fractal-like diesel soot agglomerates in the exhaust have a complex interaction with their carrier gas. This paper focuses on this complex interaction in order to assess its effect on the instruments' output. A theoretical model for the aerodynamic behavior of fractal-like agglomerates is used as a tool to assess the performance of the ELPI and the SMPS for the measurement of diesel soot particles. The model couples the aerodynamic diameter and the mobility diameter for fractal-like soot agglomerates. Visual analysis with scanning electron microscopy (SEM) aids model development and instrument performance assessment. It is concluded that the performance of both instruments is affected by the fractal-like structure of diesel soot. The ELPI, if it is set to measure the aerodynamic diameter, gives an underestimation of the apparent size of particles due to their fractal-like structure. As a result, the number of particles is overestimated. The model presented in this paper helps interpretation of the ELPIs response. The SMPS is affected by multiple charging of soot agglomerates, larger than 1000 nm, which are abundantly present in diesel exhaust gas and are not removed by the impaction stage at the input due to their small effective density. The diesel engine in this paper emits many of such particles. Multiple charging leads to an underestimation of the size of the agglomerates and hampers size classification in the instrument.

AB - The scanning mobility particle sizer (SMPS) and the electrical low-pressure impactor (ELPI) are frequently used to measure particle size distributions of combustion aerosols. The instruments are especially popular for diesel exhaust measurements since the emission of "particulate matter" is restricted by legislation. A problem is that the interpretation of the results that these instruments give is not straightforward: fractal-like diesel soot agglomerates in the exhaust have a complex interaction with their carrier gas. This paper focuses on this complex interaction in order to assess its effect on the instruments' output. A theoretical model for the aerodynamic behavior of fractal-like agglomerates is used as a tool to assess the performance of the ELPI and the SMPS for the measurement of diesel soot particles. The model couples the aerodynamic diameter and the mobility diameter for fractal-like soot agglomerates. Visual analysis with scanning electron microscopy (SEM) aids model development and instrument performance assessment. It is concluded that the performance of both instruments is affected by the fractal-like structure of diesel soot. The ELPI, if it is set to measure the aerodynamic diameter, gives an underestimation of the apparent size of particles due to their fractal-like structure. As a result, the number of particles is overestimated. The model presented in this paper helps interpretation of the ELPIs response. The SMPS is affected by multiple charging of soot agglomerates, larger than 1000 nm, which are abundantly present in diesel exhaust gas and are not removed by the impaction stage at the input due to their small effective density. The diesel engine in this paper emits many of such particles. Multiple charging leads to an underestimation of the size of the agglomerates and hampers size classification in the instrument.

KW - Agglomerates

KW - Diesel soot

KW - ELPI

KW - Fractal-like

KW - Instrument evaluation

KW - SMPS

UR - http://www.scopus.com/inward/record.url?scp=4744350284&partnerID=8YFLogxK

U2 - 10.1016/j.jaerosci.2003.11.004

DO - 10.1016/j.jaerosci.2003.11.004

M3 - Article

VL - 35

SP - 633

EP - 655

JO - Journal of Aerosol Science

JF - Journal of Aerosol Science

SN - 0021-8502

IS - 5

ER -