Design and performance of a rapid piston expansion tube for the investigation of droplet condensation 液滴凝结研究用快速活塞膨胀管的设计与性能.pdf

Experiments in Fluids 24 (1998) 300307 Springer-Verlag 1998 Design and performance of a rapid piston expansion tube for the investigation of droplet condensation F. Peters, T. Rodemann 300 Abstract A piston expansion tube (pex-tube) is described This rate is proportional to the nucleation rate and the growth which has been developed for the investigation of homogene- rate of the droplet volume. In cases of single vapor nucleation ous nucleation in a supersaturated vapor and subsequent the rate may be taken from classical nucleation theory (CNT) droplet growth. The design of the tube with periphery is or a revised version (Wilemski 1995) providing an explicit discussed as well as the underlying gasdynamics. Examples for formula. It is important, however, to have experimental the measurement of nucleation and growth rates in a binary nucleation data to check the quantitative correctness of the mixture of n-propanol/water carried in nitrogen demonstrate formula and to adjust parameters (mainly surface tension) performance and range. The focus of the paper is on the when necessary. In binary or multicomponent nucleation the determination of the nucleation state. It is shown that this state existing models provide unreliable or even unphysical results may not be based on an adiabatic expansion when helium is (Wilemski 1987). So much the more one is left to experimental used as carrier gas instead of argon or nitrogen. data. Growth models are based on the transport equations