Measurement and interpretation of growth of binary droplets suspended in a water- n-propanol-nitrogen mixture by means of a piston-expansion-tube

• Published in: International journal of heat and mass transfer Vol. 40; no. 14; pp. 3407 - 3417
• Main Authors: Rodemann, T., Peters, F.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.09.1997; Elsevier
• Subjects: Aerosols; Alcohols; Calculations; Chemistry; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Light scattering; Mathematical models; Mixtures; Nitrogen; Nucleation; Tubes (components); Vapors; Water; Water; Aerosols; Monodispersed particle; Models; Propanol; Nitrogen; Experimental study; Droplet; Supersaturated steam
• ISSN: 0017-9310; 1879-2189
• DOI: 10.1016/S0017-9310(96)00377-8

We generate a cloud of monodisperse binary droplets in a piston-expansion- tube by homogeneous nucleation and subsequent growth in a supersaturated vapor. By Mie light scattering we measure the growth rate of the droplets in the radius range from 0.16 to 3 μm. We investigate the water- n-propanol system because the growth behavior of the pure substances is very well known from previous studies. Our model calculations are an extension of a successful unary model to the binary case in which the droplet composition is treated as a variable. The calculation starts at the nucleus, passes through the transition zone about Knudsen number one and extends to the final droplet/vapor equilibrium which is only reached when vapor depletion and heat release are taken into account. The model is in good agreement with the experimental data.