James F. Ely
University Professor Emeritus
Assistant Director - Colorado Institute for Energy, Materials
and Computational Science (CIEMACS)
Research Description
Two of the most important issues in today are concern for the environment and the simultaneous need to compete in a global economy. These in turn mandate efficient design of chemical process unit operations equipment, which results in reduced capital investment, operating costs, and energy consumption - a more competitive product.
To a large degree accurate, innovative chemical process design hinges on detailed knowledge of thermophysical properties of fluid mixtures. Since materials being processed are frequently complex and the interaction between the equilibrium and nonequilibrium driving forces cannot be neglected, accurate predictive models are essential. The materials being processed today are typically highly nonideal mixtures for which our current predictive models are far from satisfactory. This is especially true when trying to accurately predict liquid-liquid and liquid-solid (or dense fluid-solid) phase transitions in asymmetric mixtures (e.g., mixtures whose components exhibit large polarity and/or size differences). In order to develop improved thermophysical property models for process simulation, I have studied a wide range of molecular-based predictive and correlative methods for the representation of fluid mixture properties, including advanced corresponding states models for phase equilibrium, single-phase equilibrium properties, and the viscosity and thermal conductivity of asymmetric mixtures.
In conjunction with these studies, I have also explored the use of computer simulation (e.g., molecular dynamics and Monte Carlo techniques) to better understand the essential physics of fluid thermophysical property behavior. Some recent results of these studies have been the development of new simulation techniques for the chemical potential, new equations of state for alternate refrigerants such as R134a, and a predictive model for the viscosity and thermal conductivity of refrigerant mixtures. I have also made experimental measurements of PVT relationships for pure fluids and mixtures as well as pure fluid dielectric constants. An experimental research program in ultra-high-precision densimetry, direct measurement of mixture component fugacities, and the measurement of mixture critical lines currently being developed.
Selected Publications
Liu, B.I., M.T. Lusk, J.F. Ely, C.A. van Duin, and W.A. Goddard, Reactive Molecular Dynamics Force Field for the Dissociation of Light Hydrocarbons on Ni(111) Mol. Sim., 2008. 34(10-15): p. 967-972.
Kiselev, S.B. and J.F. Ely, Thermodynamic properties in the critical region, in JSRAE Thermodynamic Tables. 2007. p. 40-44.
Kiselev, S.B. and J.F. Ely, HRX-SAFT Equation of State for Fluid Mixtures: New Analytical Formulation. J. Phys. Chem. C, 2007. 111(43): p. 15969-15975.
Kiselev, S.B. and J.F. Ely, Generalized crossover description of the thermodynamic and transport properties in pure fluids II. Revision and modifications. Fluid Phase Equilib., 2007. 252(1): p. 57-65.
Galamba, N., C.A.N. de Castro, and J.F. Ely, Equilibrium and nonequilibrium molecular dynamics simulations of the thermal conductivity of molten alkali halides. J. Chem. Phys., 2007. 126(20): p. 4511-4521.