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High-speed optical and laser diagnostics - Internal combustion engines and gas turbine applications

Derafshzan, Saeed LU (2023)
Abstract
Increasing demands to meet regulations on combustion emissions and their environmental impact, and the need to improve their efficiency in different applications, have been the centre of focus in research and industry for decades. Optical and laser diagnostics have been proven to be amongst the best available tools due to their remote nature and non-intrusiveness, high spatial and temporal resolution, and their ability to investigate combustion processes and emissions in ways unprecedented before. In this thesis multiple optical and laser diagnostic techniques and their application in internal combustion engines (ICE) and gas turbines are presented.
Low temperature combustion concepts in ICEs including partially premixed combustion are... (More)
Increasing demands to meet regulations on combustion emissions and their environmental impact, and the need to improve their efficiency in different applications, have been the centre of focus in research and industry for decades. Optical and laser diagnostics have been proven to be amongst the best available tools due to their remote nature and non-intrusiveness, high spatial and temporal resolution, and their ability to investigate combustion processes and emissions in ways unprecedented before. In this thesis multiple optical and laser diagnostic techniques and their application in internal combustion engines (ICE) and gas turbines are presented.
Low temperature combustion concepts in ICEs including partially premixed combustion are implemented to increase efficiency and reduce emissions. The underlying mechanisms of these improvements are studied with optical techniques and complementary computational fluid dynamics (CFD) studies. In particular, multiple injection strategies and their effects are demonstrated in a heavy-duty optical engine.
Marine engines, due to their scale and different applications are less susceptible to the electrification tendencies seen recently in light duty engine industry. Optical investigation in an optical marine engine and dual fuel setup with methane as the main fuel and diesel fuel as pilot injection, provides insight on lowering the emissions and the usage of low-carbon fuels.
Modifications and optimizations of different parts in ICEs, including piston geometry, can increase fuel efficiency and lower emissions. A novel waveshaped piston geometry and its effects on combustion processes and soot emissions are investigated with multiple optical and laser diagnostics, including natural luminosity, particle image velocimetry (PIV), and the results are compared to that of a conventional piston geometry.
Other than applications, a more diagnostic-focused study of different flow field measurements are presented. PIV is the established 2D flow field measurement technique in many applications. However, in contrast to its seemingly simple nature, it can be challenging and at times impossible to implement in certain applications. Instead of tracing particles, the same velocimetry algorithm is used on flame structures, and the semi-quantitative results are presented and compared to PIV technique.
Furthermore, these diagnostic techniques have been extensively implemented in a gas turbine model combustor. PIV technique combined with laser-induced fluorescence (LIF) of OH provides additional information about flow field and combustion processes simultaneously. The impacts of pilot flames, Hydrogen enrichment, CO2 dilution are investigated and presented. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Prof. Larmi, Martti, Aalto University, Finland.
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Fysicumarkivet A:2023:Derafshzan
pages
206 pages
publisher
Department of Physics, Lund University
defense location
Lecture Hall Rydbergsalen, Department of Physics, Professorsgatan 1, Faculty of Engineering LTH, Lund University, Lund.
defense date
2023-10-25 09:00:00
ISBN
978-91-8039-844-2
978-91-8039-843-5
language
English
LU publication?
yes
id
476595da-6e6c-46ba-a539-7f1b2ceac305
date added to LUP
2023-09-29 23:48:22
date last changed
2024-02-01 11:55:25
@phdthesis{476595da-6e6c-46ba-a539-7f1b2ceac305,
  abstract     = {{Increasing demands to meet regulations on combustion emissions and their environmental impact, and the need to improve their efficiency in different applications, have been the centre of focus in research and industry for decades. Optical and laser diagnostics have been proven to be amongst the best available tools due to their remote nature and non-intrusiveness, high spatial and temporal resolution, and their ability to investigate combustion processes and emissions in ways unprecedented before. In this thesis multiple optical and laser diagnostic techniques and their application in internal combustion engines (ICE) and gas turbines are presented.<br/>Low temperature combustion concepts in ICEs including partially premixed combustion are implemented to increase efficiency and reduce emissions. The underlying mechanisms of these improvements are studied with optical techniques and complementary computational fluid dynamics (CFD) studies. In particular, multiple injection strategies and their effects are demonstrated in a heavy-duty optical engine.<br/>Marine engines, due to their scale and different applications are less susceptible to the electrification tendencies seen recently in light duty engine industry. Optical investigation in an optical marine engine and dual fuel setup with methane as the main fuel and diesel fuel as pilot injection, provides insight on lowering the emissions and the usage of low-carbon fuels.<br/>Modifications and optimizations of different parts in ICEs, including piston geometry, can increase fuel efficiency and lower emissions. A novel waveshaped piston geometry and its effects on combustion processes and soot emissions are investigated with multiple optical and laser diagnostics, including natural luminosity, particle image velocimetry (PIV), and the results are compared to that of a conventional piston geometry.<br/>Other than applications, a more diagnostic-focused study of different flow field measurements are presented. PIV is the established 2D flow field measurement technique in many applications. However, in contrast to its seemingly simple nature, it can be challenging and at times impossible to implement in certain applications. Instead of tracing particles, the same velocimetry algorithm is used on flame structures, and the semi-quantitative results are presented and compared to PIV technique.<br/>Furthermore, these diagnostic techniques have been extensively implemented in a gas turbine model combustor. PIV technique combined with laser-induced fluorescence (LIF) of OH provides additional information about flow field and combustion processes simultaneously. The impacts of pilot flames, Hydrogen enrichment, CO2 dilution are investigated and presented.}},
  author       = {{Derafshzan, Saeed}},
  isbn         = {{978-91-8039-844-2}},
  keywords     = {{Fysicumarkivet A:2023:Derafshzan}},
  language     = {{eng}},
  month        = {{09}},
  publisher    = {{Department of Physics, Lund University}},
  school       = {{Lund University}},
  title        = {{High-speed optical and laser diagnostics - Internal combustion engines and gas turbine applications}},
  url          = {{https://lup.lub.lu.se/search/files/160053322/Thesis_Kappa_Final_Colortest.pdf}},
  year         = {{2023}},
}