SOLUTE NUCLEATION AND GROWTH IN SUPERCRITICAL FLUID MIXTURES


Abstract

This research effort is directed toward two primary scientific objectives: (1) to determine the gravitational effect on the measurement of nucleation and growth rates near a critical point and (2) to investigate the nucleation process in supercritical fluids to aid in the evaluation and development of existing theoretical models and practical applications. A nucleation pulse method will be employed for this investigation using a rapid expansion to a supersaturated state that is maintained for ÷1 ms followed by a rapid recompression to a less supersaturated state that effectively terminates nucleation while permitting growth to continue. Nucleation, which occurs during the initial supersaturated state, is decoupled from growth by producing rapid pressure changes. Thermodynamic analysis, condensation modeling, apparatus design, and optical diagnostic design necessary for the initiation of a theoretical and experimental investigation of naphthalene nucleation from supercritical CO2 have been completed.


Smedley, G.T., Wilemski, G., Rawlins, W.T., Oakes, D.B., Joshi, P., Durgin, W.W., Solute Nucleation and Growth in Supercritical Fluid Mixtures, 3rd Microgravity Fluid Physics Conference, NASA Lewis Research Center, Cleveland, OH, CP 3338, pp. 61-66, June 13, 1996.