CATTOLICA, ROBERT J
Faculty
rcattoli@ucsd.edu

Research Interests

Research Unit: Combustion

Professor Cattolica develops and employs diagnostic tools that are leading to a better understanding of the mechanics of combustion. He is extending the application of spectroscopic diagnostics in combustion, reacting flows, and gas dynamics. His research includes: spectroscopic measurements of temperature and species concentration in strained flames; plasma temperature measurements in semiconductor plasma reactors (where ions are used etch circuit features); and droplet size and velocity characteristics of pulsed fuel injectors for propulsion applications. He is currently developing laser techniques to accurately measure the chemical structure of flames including the formation of nitric oxide, a principal combustion emission. Cattolica's measurements are helping Jacobs School colleagues Kalyanansundaram Seshadri and Forman A. Williams validate the "San Diego Mechanism," a library of chemical kinetic mechanisms used to model the physical and chemical characteristics of the combustion of common fuels including the prediction of pollutant formation. The mechanism is expected to be useful for engine studies and in other areas where computerized simulations should account for the effects of varying fuel mixtures. Cattolica can provide critical perspective on matters of import to both environmental and energy policy including: the questionable use of oxygenates (ethanol and MTBE) as gasoline additives, greenhouse gas emissions, air pollution, clean-engine technology, and renewable energy from biomass.


LASHERAS, JUAN C.
Faculty
jlashera@ucsd.edu

Research Interests

Research Unit: Combustion

An aeronautical engineer by training, Professor Lasheras works at the intersection between medicine and engineering. His research interests include turbulent flows, two-phase flows and mechano-biology with special emphasis on the mechanics of cell migration and invasion. He conducts laboratory and mathematical modeling of flows relevant to a wide range of applications spanning from naval hydrodynamics to propulsion and vascular hemodynamics. He has studied the complex interaction between the mechanical stimuli and the pathophysiology of vessel remodeling responsible for the enlargement of cerebrovascular and abdominal aortic aneurysms. He currently works on several aspects of cell mechanics, including, cell mechano-transduction, cell migration and invasion.


SANCHEZ, ANTONIO L
Faculty
alsp@ucsd.edu

Research Interests

Research Unit: Combustion

Prof. Sanchez’s research falls within the general field of chemically reacting flows, including research topics related to clean combustion technologies, aerospace propulsion devices, and safety hazards in the built environment. He is interested in fundamental problems that involve the interplay of fluid mechanics, transport processes, and chemical reactions, in particular those emerging in practical combustion systems. His research approach takes advantage of the disparity of the length and time scales encountered in these complex problems to simplify the solutions, often by application of asymptotic methods that help to identify simpler sub-problems and serve to extract the fundamental underlying physics. His work has covered a large number of different combustion and fluid-mechanical problems, including a wide range of reactive phenomena of technological importance such as spontaneous and forced ignition, deflagrations, detonations, diffusion flames, partially premixed combustion, and spray combustion.


SESHADRI, KALYANASUNDARAM
Faculty
kseshadr@ucsd.edu

Research Interests

Research Unit: Combustion

Professor Seshadri is an expert in combustion. He is interested in the chemical inhibition of flames, the combustion of diesel fuels and solid propellants, the mechanisms involved in the formation of pollutants, and the destruction of toxic compounds. He has helped demonstrate the usefulness of asymptotic analysis in the science of combustion. Asymptotic analysis employs the mathematical concept of a limit to efficiently identify critical boundaries, reactions, or other factors dominant in complex non-linear natural phenomena. In 1998, Seshadri applied an asymptotic analysis that succeeded in singling out the most critical interaction among hundreds ensuing when the superior industrial fire suppressant Halon 1301 extinguishes a flame. Halon 1301 is widely used by the military to quench fires in planes. But the chemical, also known as bromotrifluoromethane or CF3Br is no longer manufactured because it damages the Earth's protective ozone layer. Because Seshadri implicated bromine as critical to Halon 1301's fire-suppressing efficiency, and since bromine is the element in Halon 1301 that destroys ozone, the work signaled that the search for alternatives should switch from naturally occurring elements toward development of non-toxic synthetic substances. Dr. Seshadri can speak about many combustion related topics, including using fire to eliminate biochemical warfare agents.


TALKE, FRANK E
Faculty
ftalke@ucsd.edu

Research Interests

Research Unit: Combustion

In the last 55 years, areal density of data storage in rigid disks has increased 100 million fold to more than 500 Gbits (500 billion bits) per inch square. The next mile stone, 1 Tbit/square inch, is near and researchers are working on 10 Terabits (ten trillion bits) per square inch areal density. New techniques are required to design devices with moving parts orders of magnitude smaller than those typically encountered by mechanical engineers. As head of the Tribology and Mechanics Lab at UCSD’s Center for Magnetic Recording Research, Professor Talke is at the forefront of research that takes places where borders blur between mechanics, physics, and chemistry. For example, storage density of one Terabit/square inch will require read-write heads in a disk drive to fly within one or two nanometers from the disk media. Active flying height control by thermal activation of the magnetic read/write head is one of the possibilities to achieve this. A flying height of one or two nanometers is so close that adhesion forces between slider and disk must be considered, that lubricant-materials interactions (stiction) come into play, and that the slightest mechanical disturbance can cause the slider to lose the desired track. Areas of expertise for Talke are the mechanics of the head/disk interface in tape and disk drives, the tribology and surface interactions of heads and recording media, strategies to reduce the flying height, the physics and chemistry of lubricants, modeling and analysis of the flying characteristics of sliders, and high precision instrumentation to assess and measure slider motion, slider dynamics and wear at the head disk interface.


WILLIAMS, FORMAN A.
Faculty
fwilliam@ucsd.edu

Research Interests

Research Unit: Combustion

Professor Williams' studies range from investigations into the fundamental nature of energy and combustion to practical applications in energy conservation and production, as well as pollution control. Among other things, he looks at the structures of flames employing both detailed and modeled chemistry, conducting small-scale laminar combustion experiments to measure ignition and extinction. Williams' work in combustion has led to a greater understanding of pollutants. He has focused on the mechanisms of production of NOx emissions (oxides of nitrogen), which can be used to decrease pollution from automobiles. Williams has designed fundamental combustion experiments on the space shuttle and in the space station to look at the effects of gravity or microgravity on flames. By studying droplet and spray combustion for propulsion, more efficient rocket engines have been addressed. Most recently, Williams has been looking at fire safety and providing a San Diego chemical kinetic mechanism for use in combustion problems.