Applications of a Mid-IR Quantum Cascade Laser in Gas Sensing Research

Handle URI:
http://hdl.handle.net/10754/555599
Title:
Applications of a Mid-IR Quantum Cascade Laser in Gas Sensing Research
Authors:
Sajid, Muhammad Bilal ( 0000-0002-6341-0918 )
Abstract:
Laser absorption based sensors are extensively used in a variety of gas sensing areas such as combustion, atmospheric research, human breath analysis, and high resolution infrared spectroscopy. Quantum cascade lasers have recently emerged as high resolution, high power laser sources operating in mid infrared region and can have wide tunability range. These devices provide an opportunity to access stronger fundamental and combination vibrational bands located in mid infrared region than previously accessible weaker overtone vibrational bands located in near infrared region. Spectroscopic region near 8 µm contains strong vibrational bands of methane, acetylene, hydrogen peroxide, water vapor and nitrous oxide. These molecules have important applications in a wide range of applications. This thesis presents studies pertaining to spectroscopy and combustion applications. Advancements in combustion research are imperative to achieve lower emissions and higher efficiency in practical combustion devices such as gas turbines and engines. Accurate chemical kinetic models are critical to achieve predictive models which contain several thousand reactions and hundreds of species. These models need highly reliable experimental data for validation and improvements. Shock tubes are ideal devices to obtain such information. A shock tube is a homogenous, nearly constant volume, constant pressure, adiabatic and 0-D reactor. In combination with laser absorption sensors, shock tubes can be used to measure reaction rates and species time histories of several intermediates and products formed during pyrolysis and oxidation of fuels. This work describes measurement of the decomposition rate of hydrogen peroxide which is an important intermediate species controlling reactivity of combustion system in the intermediate temperature range. Spectroscopic parameters (linestrengths, broadening coefficients and temperature dependent coefficients) are determined for various transitions of acetylene. Furthermore, methane and acetylene sensors are developed for shock tube applications. The application of these sensors (along with an ethylene sensor) has been demonstrated to measure these species during the pyrolysis of n-pentane and iso-pentane.
Advisors:
Farooq, Aamir ( 0000-0001-5296-2197 )
Committee Member:
Roberts, William L.; Chung, Suk Ho ( 0000-0001-8782-312X ) ; Pang, Genny
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Program:
Mechanical Engineering
Issue Date:
May-2015
Type:
Dissertation
Appears in Collections:
Dissertations; Physical Sciences and Engineering (PSE) Division; Mechanical Engineering Program

Full metadata record

DC FieldValue Language
dc.contributor.advisorFarooq, Aamiren
dc.contributor.authorSajid, Muhammad Bilalen
dc.date.accessioned2015-05-24T06:52:55Zen
dc.date.available2015-05-24T06:52:55Zen
dc.date.issued2015-05en
dc.identifier.urihttp://hdl.handle.net/10754/555599en
dc.description.abstractLaser absorption based sensors are extensively used in a variety of gas sensing areas such as combustion, atmospheric research, human breath analysis, and high resolution infrared spectroscopy. Quantum cascade lasers have recently emerged as high resolution, high power laser sources operating in mid infrared region and can have wide tunability range. These devices provide an opportunity to access stronger fundamental and combination vibrational bands located in mid infrared region than previously accessible weaker overtone vibrational bands located in near infrared region. Spectroscopic region near 8 µm contains strong vibrational bands of methane, acetylene, hydrogen peroxide, water vapor and nitrous oxide. These molecules have important applications in a wide range of applications. This thesis presents studies pertaining to spectroscopy and combustion applications. Advancements in combustion research are imperative to achieve lower emissions and higher efficiency in practical combustion devices such as gas turbines and engines. Accurate chemical kinetic models are critical to achieve predictive models which contain several thousand reactions and hundreds of species. These models need highly reliable experimental data for validation and improvements. Shock tubes are ideal devices to obtain such information. A shock tube is a homogenous, nearly constant volume, constant pressure, adiabatic and 0-D reactor. In combination with laser absorption sensors, shock tubes can be used to measure reaction rates and species time histories of several intermediates and products formed during pyrolysis and oxidation of fuels. This work describes measurement of the decomposition rate of hydrogen peroxide which is an important intermediate species controlling reactivity of combustion system in the intermediate temperature range. Spectroscopic parameters (linestrengths, broadening coefficients and temperature dependent coefficients) are determined for various transitions of acetylene. Furthermore, methane and acetylene sensors are developed for shock tube applications. The application of these sensors (along with an ethylene sensor) has been demonstrated to measure these species during the pyrolysis of n-pentane and iso-pentane.en
dc.language.isoenen
dc.subjectChemical Kineticen
dc.subjectSpectroscopyen
dc.subjectDuantum Cascade Laseren
dc.subjectCias Sensingen
dc.subjectCombustionen
dc.subjectShock Tubeen
dc.titleApplications of a Mid-IR Quantum Cascade Laser in Gas Sensing Researchen
dc.typeDissertationen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
thesis.degree.grantorKing Abdullah University of Science and Technologyen_GB
dc.contributor.committeememberRoberts, William L.en
dc.contributor.committeememberChung, Suk Hoen
dc.contributor.committeememberPang, Gennyen
thesis.degree.disciplineMechanical Engineeringen
thesis.degree.nameDoctor of Philosophyen
dc.person.id115851en
All Items in KAUST are protected by copyright, with all rights reserved, unless otherwise indicated.