The objective of this work is to design a condensation nucleus counter capable of counting particles as small as 0.003 um at pressures ranging from 10 to 1000 mbar. The heat and mass transfer processes in the condensation nucleus counter will be modeled numerically. Condensational droplet growth with heat dissipation will be modelled analytically. The model will be verified to the extent possible by comparison with existing models and data from a condensation nucleus counter which has been used for stratospheric particle measurements. Model results will be used to design an improved condensation nucleus counter. Parameters to be optimized include flow rates, working fluid, condenser and saturator temperatures and condenser length.
