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Thermometry Using Laser-Induced Emission from Thermographic Phosphors: Development and Applications in Combustion

Omrane, Alaa LU (2005)
Abstract
Temperature is a fundamental thermodynamic parameter used to describe physical, chemical and biological processes. Much effort is made to measure temperature accurately in a wide variety of applications, making temperature one of the most extensively measured parameters. In combustion as in many other applications, temperature plays a substantial role in helping to maintain an efficient and clean environment. Being able to measure temperature accurately in combustion and in fire-related applications is important for giving a better understanding of heat transfer phenomena and improving existing models.



A method based on the spectroscopy of inorganic luminescent materials is described here and is employed in experiments... (More)
Temperature is a fundamental thermodynamic parameter used to describe physical, chemical and biological processes. Much effort is made to measure temperature accurately in a wide variety of applications, making temperature one of the most extensively measured parameters. In combustion as in many other applications, temperature plays a substantial role in helping to maintain an efficient and clean environment. Being able to measure temperature accurately in combustion and in fire-related applications is important for giving a better understanding of heat transfer phenomena and improving existing models.



A method based on the spectroscopy of inorganic luminescent materials is described here and is employed in experiments related to combustion. The method involves use of thermographic phosphors which enable remote temperature diagnostics to be performed with a high degree of sensitivity and accuracy. The technique is superior to those based on thermocouples and pyrometry, particularly in the vicinity of flames and when the measured surface is subjected to random movements. Thermographic phosphors are applied here to temperature measurements in one-point and in two-dimensions within flamespread scenarios. Results obtained in this small-scale flamespread scenario served as input data to various subprojects within the framework of a more extensive flamespread project. The technique was also employed in pyrolysis experiments involving different construction materials and polymers. The experiments included simultaneous measurements of surface temperature and mass-loss rate for the verification of a pyrolysis model applied to the decomposition of these materials. Thermographic phosphors have the property of being insensitive to variations in pressure up to 1 GPa. This property extends the use and development of thermographic thermometry to other domains, such as internal combustion engines. Surface temperatures of the piston and valves of gasoline engines of the direct-injection type were investigated. The temperature was measured at one point and in two dimensions inside the combustion chamber. The results suggest that developing the technique for thermometry of diesel engine pistons could be promising. Simultaneous measurements of piston temperature were performed with use of thermographic phosphors and thermocouples. The complex procedures required to implement the use of thermocouples inside an engine make thermocouples an expensive choice, especially with the only very limited possibilities this provides of investigating different engine geometries and components. Thermographic phosphors were also employed in gas turbine applications. Temperature imaging of the afterburner of a full-size aircraft engine was performed in combination with fuel visualisation by use of laser-induced fluorescence. The experiments were aimed at studying the effects of various engine loads on wall temperatures and fuel efficiency.



Thermographic phosphors were used to study the temperature of droplets in relation to spray generation. In spray dynamics, temperature is a crucial parameter for gaining an understanding of atomisation, of evaporation and of heat convection from the surrounding gases. Although the technique is in first stage of its development, promising results for mono-dispersed droplets and sprays were obtained. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Dr Allison, Stephen, Oak Ridge National Laboratory, USA
organization
publishing date
type
Thesis
publication status
published
subject
keywords
framdrivningssystem, Motorer, Motors and propulsion systems, Laser technology, Laserteknik, Teknik, Technological sciences, Physics, Pyrolysis, Flame spread, Droplet, Engine, Imaging, Temperature, Thermographic phosphors, Combustion, Fysik, Laser diagnostics
pages
276 pages
publisher
KFS AB
defense location
Room B, Department of Physics Professorsgatan 1, Lund Institute of Technology
defense date
2005-04-15 10:15
external identifiers
  • other:ISRN: LUTFD2/TFCP--105--SE
ISSN
1102-8718
ISBN
91-628-6469-6
language
English
LU publication?
yes
id
a360508c-765a-49b2-8b48-3e46f048857d (old id 544543)
date added to LUP
2007-10-13 12:55:53
date last changed
2016-09-19 08:44:54
@phdthesis{a360508c-765a-49b2-8b48-3e46f048857d,
  abstract     = {Temperature is a fundamental thermodynamic parameter used to describe physical, chemical and biological processes. Much effort is made to measure temperature accurately in a wide variety of applications, making temperature one of the most extensively measured parameters. In combustion as in many other applications, temperature plays a substantial role in helping to maintain an efficient and clean environment. Being able to measure temperature accurately in combustion and in fire-related applications is important for giving a better understanding of heat transfer phenomena and improving existing models.<br/><br>
<br/><br>
A method based on the spectroscopy of inorganic luminescent materials is described here and is employed in experiments related to combustion. The method involves use of thermographic phosphors which enable remote temperature diagnostics to be performed with a high degree of sensitivity and accuracy. The technique is superior to those based on thermocouples and pyrometry, particularly in the vicinity of flames and when the measured surface is subjected to random movements. Thermographic phosphors are applied here to temperature measurements in one-point and in two-dimensions within flamespread scenarios. Results obtained in this small-scale flamespread scenario served as input data to various subprojects within the framework of a more extensive flamespread project. The technique was also employed in pyrolysis experiments involving different construction materials and polymers. The experiments included simultaneous measurements of surface temperature and mass-loss rate for the verification of a pyrolysis model applied to the decomposition of these materials. Thermographic phosphors have the property of being insensitive to variations in pressure up to 1 GPa. This property extends the use and development of thermographic thermometry to other domains, such as internal combustion engines. Surface temperatures of the piston and valves of gasoline engines of the direct-injection type were investigated. The temperature was measured at one point and in two dimensions inside the combustion chamber. The results suggest that developing the technique for thermometry of diesel engine pistons could be promising. Simultaneous measurements of piston temperature were performed with use of thermographic phosphors and thermocouples. The complex procedures required to implement the use of thermocouples inside an engine make thermocouples an expensive choice, especially with the only very limited possibilities this provides of investigating different engine geometries and components. Thermographic phosphors were also employed in gas turbine applications. Temperature imaging of the afterburner of a full-size aircraft engine was performed in combination with fuel visualisation by use of laser-induced fluorescence. The experiments were aimed at studying the effects of various engine loads on wall temperatures and fuel efficiency.<br/><br>
<br/><br>
Thermographic phosphors were used to study the temperature of droplets in relation to spray generation. In spray dynamics, temperature is a crucial parameter for gaining an understanding of atomisation, of evaporation and of heat convection from the surrounding gases. Although the technique is in first stage of its development, promising results for mono-dispersed droplets and sprays were obtained.},
  author       = {Omrane, Alaa},
  isbn         = {91-628-6469-6},
  issn         = {1102-8718},
  keyword      = {framdrivningssystem,Motorer,Motors and propulsion systems,Laser technology,Laserteknik,Teknik,Technological sciences,Physics,Pyrolysis,Flame spread,Droplet,Engine,Imaging,Temperature,Thermographic phosphors,Combustion,Fysik,Laser diagnostics},
  language     = {eng},
  pages        = {276},
  publisher    = {KFS AB},
  school       = {Lund University},
  title        = {Thermometry Using Laser-Induced Emission from Thermographic Phosphors: Development and Applications in Combustion},
  year         = {2005},
}