Comparison of the SidePak™ personal monitor with the Aerosol Particle Sizer (APS)

Abstract. Aerosol characteristics can be measured with different instruments providing observations that are not trivially inter-comparable. Extended Kalman Filter (EKF) is introduced here as a method to estimate aerosol particle number size distributions from multiple simultaneous observations. The focus here in Part 1 of the work was on general aspects of EKF in the context of Differential Mobility Particle Sizer (DMPS) measurements. Additional instruments and their implementations are discussed in Part 2 of the work. University of Helsinki Multi-component Aerosol model (UHMA) is used to propagate the size distribution in time. At each observation time (10 min apart), the time evolved state is updated with the raw particle mobility distributions, measured with two DMPS systems. EKF approach was validated by calculating the bias and the standard deviation for the estimated size distributions with respect to the raw measurements. These were compared to corresponding bias and standard deviation values for distributions calculated with a mathematical inversion method. Despite the assumptions made in the EKF implementation, EKF was found to be more accurate than the mathematical inversion in terms of bias, and compatible in terms of standard deviation. Potential further improvements of the EKF implementation are discussed.

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Estimation of aerosol particle number distributions with Kalman Filtering – Part 1: Theory, general aspects and statistical validity

Atmospheric Chemistry and Physics ◽

10.5194/acp-12-11767-2012 ◽

2012 ◽

Vol 12 (24) ◽

pp. 11767-11779 ◽

Cited By ~ 2

Author(s):

T. Viskari ◽

E. Asmi ◽

P. Kolmonen ◽

H. Vuollekoski ◽

T. Petäjä ◽

...

Keyword(s):

Standard Deviation ◽

Aerosol Particle ◽

Particle Number ◽

Observation Time ◽

Kernel Matrix ◽

Size Distributions ◽

Aerosol Model ◽

Particle Mobility ◽

Particle Sizer ◽

General Aspects

Abstract. Aerosol characteristics can be measured with different instruments providing observations that are not trivially inter-comparable. Extended Kalman Filter (EKF) is introduced here as a method to estimate aerosol particle number size distributions from multiple simultaneous observations. The focus here in Part 1 of the work was on general aspects of EKF in the context of Differential Mobility Particle Sizer (DMPS) measurements. Additional instruments and their implementations are discussed in Part 2 of the work. University of Helsinki Multi-component Aerosol model (UHMA) is used to propagate the size distribution in time. At each observation time (10 min apart), the time evolved state is updated with the raw particle mobility distributions, measured with two DMPS systems. EKF approach was validated by calculating the bias and the standard deviation for the estimated size distributions with respect to the raw measurements. These were compared to corresponding bias and standard deviation values for particle number size distributions obtained from raw measurements by a inversion of the instrument kernel matrix method. Despite the assumptions made in the EKF implementation, EKF was found to be more accurate than the inversion of the instrument kernel matrix in terms of bias, and compatible in terms of standard deviation. Potential further improvements of the EKF implementation are discussed.

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Application of Acoustic Agglomeration Technology to Improve the Removal of Submicron Particles from Vehicle Exhaust

Symmetry ◽

10.3390/sym13071200 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1200

Author(s):

Inga Garbarienė ◽

Vadimas Dudoitis ◽

Vidmantas Ulevičius ◽

Kristina Plauškaitė-Šukienė ◽

Artūras Kilikevičius ◽

...

Keyword(s):

Aerosol Particle ◽

Particle Number ◽

Combustion Engine ◽

Exhaust System ◽

Ambient Air ◽

Submicron Particles ◽

Vehicle Exhaust ◽

Scanning Mobility Particle Sizer ◽

Symmetric Methods ◽

Particle Sizer

The natural processes of interactions between aerosol particles in the ambient air through which they agglomerate is a vast area of chamber research and are inherent to many industries and are often inter-connected with transport engineering. Further improvement of symmetric methods for aerosol particle number and mass concentration reduction made it possible to create various synergic techniques. The study used a 1.9 TDI diesel internal combustion engine, which was supplied with diesel (D100) and second-generation biofuels (NExBTL100) with the EGR exhaust system on and off. Measurements were performed using a Bruel and Kjær “Type 9727” system for measurement of vibrations, a scanning mobility particle sizer (SMPS) and an original agglomeration chamber. The three modes of particle size distributions were observed in the size range from 10 to 470 nm for both D100 and NExBTL100 fuels with and without the use of the EGR system. The application of 21.3 kHz frequency sound with SPL 144.1 dB changed the NExBTL100 generated aerosol particle number concentration but did not sufficiently affect the concentration of D100 emitted particles. The greatest agglomeration effect (21.7 ± 10.0%) was observed in the range of extremely small NExBTL100 derived particles (10–70 nm) when used in combination with an EGR system.

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Real-Time Aerosol Density Determination Utilizing a Modified Scanning Mobility Particle Sizer—Aerosol Particle Mass Analyzer System

Aerosol Science and Technology ◽

10.1080/02786820902832960 ◽

2009 ◽

Vol 43 (7) ◽

pp. 673-678 ◽

Cited By ~ 84

Author(s):

Quentin G. J. Malloy ◽

Shunsuke Nakao ◽

Li Qi ◽

Rebecca Austin ◽

Clayton Stothers ◽

...

Keyword(s):

Real Time ◽

Aerosol Particle ◽

Particle Mass ◽

Mass Analyzer ◽

Scanning Mobility Particle Sizer ◽

Density Determination ◽

Particle Sizer

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Analysis of particle size distribution changes between three measurement sites in Northern Scandinavia

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-13-9401-2013 ◽

2013 ◽

Vol 13 (4) ◽

pp. 9401-9442 ◽

Cited By ~ 1

Author(s):

R. Väänänen ◽

E.-M. Kyrö ◽

T. Nieminen ◽

N. Kivekäs ◽

H. Junninen ◽

...

Keyword(s):

Particle Size ◽

Size Distribution ◽

Aerosol Particle ◽

Particle Growth ◽

Particle Formation ◽

Aerosol Size Distribution ◽

New Particle Formation ◽

Air Masses ◽

Aerosol Dynamics ◽

Particle Sizer

Abstract. We investigated atmospheric aerosol particle dynamics in a boreal forest zone in Northern Scandinavia. We used aerosol size distribution data measured with either a Differential Mobility Particle Sizer (DMPS) or Scanning Mobility Particle Sizer (SMPS) at three stations (Värriö, Pallas and Abisko), and combined these data with the HYSPLIT air mass trajectory analysis. We compared three approaches: analysis of new particle formation events, investigation of air masses transport from the ocean to individual stations with different over-land transport times, and analysis of changes in aerosol particle size distributions during the air masses transport from one measurement station to another. Aitken mode particles were found to have an apparent average growth rate of 0.6–0.7 nm h−1 when the air masses travelled over land. Particle growth rates during the NPF events were 3–6 times higher than the apparent particle growth. When comparing aerosol dynamics between the different stations for different over-land transport times, no major differences were found except that in Abisko the new particle formation events were observed to take place in air masses having shorter over-land times than at the other stations. We speculate that this is related to the meteorological differences along the paths of air masses caused by the land surface topology. When comparing between air masses travelling the east-to-west direction to those traveling the west-to-east directions, clear differences in the aerosol dynamics were seen. Our results suggest that the condensation growth has an important role in aerosol dynamics also when new particle formation is not evident.

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Analysis of particle size distribution changes between three measurement sites in northern Scandinavia

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-11887-2013 ◽

2013 ◽

Vol 13 (23) ◽

pp. 11887-11903 ◽

Cited By ~ 16

Author(s):

R. Väänänen ◽

E.-M. Kyrö ◽

T. Nieminen ◽

N. Kivekäs ◽

H. Junninen ◽

...

Keyword(s):

Mass Transport ◽

Aerosol Particle ◽

Growth Rates ◽

Particle Number ◽

Particle Growth ◽

Size Distributions ◽

Air Mass ◽

Air Masses ◽

Aerosol Dynamics ◽

Particle Sizer

Abstract. We investigated atmospheric aerosol particle dynamics in a boreal forest zone in northern Scandinavia. We used aerosol number size distribution data measured with either a differential mobility particle sizer (DMPS) or scanning mobility particle sizer (SMPS) at three stations (Värriö, Pallas and Abisko), and combined these data with the HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory) air mass trajectory analysis. We compared three approaches: analysis of new particle formation events, investigation of aerosol particle number size distributions during the air mass transport from the ocean to individual stations with different overland transport times, and analysis of changes in aerosol particle number size distributions during the air mass transport from one measurement station to another. Aitken-mode particles were found to have apparent average growth rates of 0.6–0.7 nm h−1 when the air masses traveled over land. Particle growth rates during the new particle formation (NPF) events were 3–6 times higher than the apparent particle growth during the summer period. When comparing aerosol dynamics for different overland transport times between the different stations, no major differences were found, except that in Abisko the NPF events were observed to take place in air masses with shorter overland times than at the other stations. We speculate that this is related to the meteorological differences along the paths of air masses caused by the land surface topology. When comparing air masses traveling in an east-to-west direction with those traveling in a west-to-east direction, clear differences in the aerosol dynamics were seen. Our results suggest that the condensation growth has an important role in aerosol dynamics even when NPF is not evident.

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