Abstract
Aerosol particles impact climate and human health, with properties such
as particle size and chemical composition playing a key role.
Nanoparticles (particles with a diameter below 50 nanometers) are of
particular concern for human health.
Combustion engines emit particles that deteriorate air quality, especially in urban areas, where road transport is the most significant source of nanoparticles. In the first part of the thesis, particle emissions from a farming tractor and a heavy-duty truck were characterized. The effects of different fuels and lubricating oils on particle emissions were also investigated.
Key findings of the particle emission research include a thorough description of the emitted particles and the impact of fuels and lubricating oils on emissions. With both vehicles, a significant fraction of the particles were found to be in the nanoparticle size range, and this fraction was found to be especially sensitive to the fuel and lubricating oil used. It was concluded that particle emissions can be significantly reduced by changing to a stricter-quality fuel. Changing the lubricating oil was found to have an effect of comparable magnitude to changing the fuel.
In the second part of this thesis, new methods for measuring nanoparticle properties were presented. The methods were tested and characterized in a laboratory setting. The Aerosol Gas Exchange System (AGES) changes the carrier gas of, and thermally treats the particles with minimal losses. The particle losses of AGES for 6 nm particles were below 5 %, and gas removal efficiencies exceeding 90 % were obtained for light compounds (e.g. water). Soot Particle Agglomeration Inlet (SPAI) is used in tandem with Soot Particle Aerosol Mass Spectrometer (SP-AMS) to measure the chemical composition of nanoparticles near real-time. Up to a 35-fold increase in nanoparticle detection was achieved by applying SPAI. The developed methods have applications also beyond engine exhaust particle measurement.
Combustion engines emit particles that deteriorate air quality, especially in urban areas, where road transport is the most significant source of nanoparticles. In the first part of the thesis, particle emissions from a farming tractor and a heavy-duty truck were characterized. The effects of different fuels and lubricating oils on particle emissions were also investigated.
Key findings of the particle emission research include a thorough description of the emitted particles and the impact of fuels and lubricating oils on emissions. With both vehicles, a significant fraction of the particles were found to be in the nanoparticle size range, and this fraction was found to be especially sensitive to the fuel and lubricating oil used. It was concluded that particle emissions can be significantly reduced by changing to a stricter-quality fuel. Changing the lubricating oil was found to have an effect of comparable magnitude to changing the fuel.
In the second part of this thesis, new methods for measuring nanoparticle properties were presented. The methods were tested and characterized in a laboratory setting. The Aerosol Gas Exchange System (AGES) changes the carrier gas of, and thermally treats the particles with minimal losses. The particle losses of AGES for 6 nm particles were below 5 %, and gas removal efficiencies exceeding 90 % were obtained for light compounds (e.g. water). Soot Particle Agglomeration Inlet (SPAI) is used in tandem with Soot Particle Aerosol Mass Spectrometer (SP-AMS) to measure the chemical composition of nanoparticles near real-time. Up to a 35-fold increase in nanoparticle detection was achieved by applying SPAI. The developed methods have applications also beyond engine exhaust particle measurement.
| Original language | English |
|---|---|
| Place of Publication | Tampere |
| Publisher | Tampere University |
| ISBN (Electronic) | 978-952-03-3582-3 |
| ISBN (Print) | 978-952-03-3581-6 |
| Publication status | Published - 2024 |
| Publication type | G5 Doctoral dissertation (articles) |
Publication series
| Name | Tampere University Dissertations - Tampereen yliopiston väitöskirjat |
|---|---|
| Volume | 1082 |
| ISSN (Print) | 2489-9860 |
| ISSN (Electronic) | 2490-0028 |
