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Sensitive diagnostics for reaction kinetics

Increasingly stringent emission regulations, global warming, and depleting fossil fuel
resources are driving the design of combustion systems towards extreme operating
conditions. Ultra-lean fuel mixtures, very high pressures, and low temperature
combustion are some of the directions being pursued currently. In such domains, fuel
chemistry and reaction kinetics play critical role in the design and optimization of
combustion systems.
Common facilities for the study of homogeneous chemical kinetics include shock tubes,
rapid compression machines, combustion bombs, flow reactors, well-stirred reactors, and
motored engines. Of these, shock tubes provide the most ideal environment to investigate
fuel chemistry in the absence of heat transfer and fluid dynamic effects. Shock tubes are
generally used to measure ignition delay times of fuel/oxidizer mixtures under varying
conditions of temperature, pressure, and stoichiometry. However, when coupled with in-situ sensitive diagnostics, shock tubes can also provide reaction rate constant
measurements and species time-history profiles. Such data are extremely useful in the
development and validation of detailed chemical kinetic models.
This talk will feature some latest diagnostic developments for sensitive detection of gas
temperature and important combustion species, such as acetylene, ethylene, carbon
monoxide, hydrogen peroxide, hydroxyl radical and free electrons. Advanced optical
strategies, such as intrapulse chirping, wavelength modulation, cavity ringdown and
microwave interferometry are employed. It will be demonstrated how the detection of
these species enables deeper insight into complex reaction mechanisms.
Speaker Bio:
Prof. Farooq received his PhD from the Mechanical Engineering Department at Stanford
University in 2010. He is the principal investigator of the Chemical Kinetics and Laser
Sensors Laboratory at King Abdullah University of Science and Technology (KAUST).
He has authored nearly 50 refereed journal articles and has presented at a number of
conferences. His research interests are in the areas of energy, combustion chemistry,
spectroscopy, and laser-based sensors. His group carries out experimental chemical
kinetics research using shock tubes, rapid compression machine and optical diagnostics.
Dr. Farooq also focuses on novel spectroscopic strategies to develop sensors for
biomedical and environment-monitoring applications.