Current research programs include analysis and design of mechanical systems, such as high performance machinery and robotic manipulators, and mechanisms, including dynamics, motion, control, and vibration-related problems. The curriculum in the computer-aided design (CAD) area is a combination of teaching and learning experience through projects involving design optimization, computer graphics, and computer codes applications. Applied courses emphasize case studies, finite element methods, and computer graphics.
The use of composite materials requires the understanding of deformation mechanisms and the long-term durability in applications. Experimental and computational investigations are carried out to study various aspects of composites. These include delamination of laminates and integrated damage sensing systems, the durability and degradation of composites exposed to long-term environmental conditions such as simulated sunlight and corrosive solutions, analysis of fracture and failure mechanisms, micro and nanoscale in-situ testing, nanocomposite mechanical characterization, and impact and shock loading. Equipment includes computational facilities, multi-scale mechanical testing instruments, environmental exposure chambers, and impulse loading instruments. There is currently ongoing collaborative research with Materials Science and Engineering.
Various aspects of deformation in advanced materials and composite structures are studied with emphasis on their failure behavior. In particular, fracture mechanisms of embedded flaws in coatings and thin films, and interlaminar delamination in laminates are investigated with large-scale computational simulations. In addition the stability of complex shell structures is studied with an emphasis on establishing rigorous techniques for understanding the dominant deformation modes leading to buckling and collapse. Current research issues addressed include nonlinear buckling mode interactions in stiffened shells and inelastic material behavior in deformation localization mechanisms observed in shell collapse experiments.
The experimental program involves development of various optical techniques of strain analysis including moire methods, laser and white-light speckle methods, holographic interferometry, photoelasticity, and classical interferometry. A major goal of the experimental program is to apply these methods to solid mechanics problems such as fracture, wave propagation, metal forming, flexor, and vibration. The experimental mechanics equipment includes various lasers, high-speed digitized cameras, a scanning electron microscope, and many other optical electro-optical devices in various research laboratories.
Current topics include advanced combustor design and flow control, and the behavior of chemically reacting species in turbulent flows. Numerical and theoretical studies include direct simulation of turbulent flows and turbulent transport at modest Reynolds numbers, stochastic modeling of the turbulent transport of temperature, and spectral closure approximations for chemically reactive flows. Current Experimental research facilities include water tunnel and channel, wind tunnels, and a heated jet. Instrumentation available includes laser-Doppler and fluorescence systems. Reactive flow, turbulence, experimental fluid mechanics, combustion, computational fluid dynamics, statistical mechanics and thermodynamics, efficient energy conversion, convective heat transfer, heat transfer in porous media.
Heat Transfer and Advanced Energy Systems
The graduate program in heat transfer consists of advanced studies in the fundamentals and applications of heat conduction, convection and thermal radiation, fluid mechanics, numerical analysis, thermodynamics, and experimental techniques. Ongoing research includes measurement of thermophysical properties, laser-material interaction, materials processing, and heat transfer in advanced energy systems. Active research is also conducted on various aspects of crystal growth, advanced sensors, photovoltaic technology, hydrate system, nuclear fuels, fuel cells, wind energy and biomass energy.
The design of heat engines, as well as most industrial processes that involve fluids, requires accurate, convenient-to-implement methods for predicting and correlating the thermodynamic properties of the fluids present in the process. Our program is designed to provide students with the analytical tools needed to model and predict the thermophysical properties of fluids. Current studies include the development of statistical mechanical techniques to study the relation between intermolecular forces and the thermodynamic, dielectric, optical, and transport properties of fluids, fluid mixtures, and suspension. Research is also being conducted on combustion heat engines, aiming at achieving high engine efficiency and engine performance. In a different research direction, methodological issues of thermodynamic theory is being examined leading to the argument that theoretical self-consistency requires thermodynamic theory to be based on both the "descriptive is" statements of thermodynamic laws and the "prescriptive how" statements of operational principles—with a broad range of implication in technology and biological sciences and in philosophy of science following from this argument.
Internal Combustion Engines
Internal Combustion Engines are the dominant power generation and propulsion systems in ground transportation, locomotive, and marine applications. Global efficiency and emissions regulations have accelerated research towards understanding combustion processes for improving the efficiency and reducing emissions formation from engines. Combustion processes depend on parameters such as gas exchange, spray and mixture formation, ignition, heat release, heat transfer, and knock, and are studied on spark-ignition and compression-ignition architectures using conventional and alternative fuels. Research incorporates a wide range of methods including 3-D CFD modeling, 0-D/1-D modeling, and experimental testing, and utilizes principles of thermodynamics, fluid mechanics, heat transfer, chemistry, and numerical analysis.