GAS-DYNAMIC AND INFRARED SPECTROSCOPIC MEASUREMENTS IN A CONDENSING FLOW OF A SULFUR HEXAFLUORIDE ARGON MIXTURE

Homogeneous nucleation and condensation of SF6 in supersonic nozzle flows have been investigated experimentally by static pressure measurements and infrared spectroscopy. The application of high resolution diode laser spectroscopy has allowed us to determine the concentration of SF 6 monomers in the precondensation supersaturated region for the first time. The gasdynamic measurements show that disturbances of the flow caused by SF6 condensation are very weak. The spectroscopic results confirmed the belief, based on the classical kinetics of nucleation, that monomers are not appreciably depleted prior to the onset of condensation by homogeneous nucleation. © 1979 American Institute of Physics.