In order to make reliable measurements of water droplet growth in a thermal diffusion cloud chamber, it is essential to have a detailed picture of all transient behavior and edge effects associated with the temperature and diffusion fields within the chamber. In the application of a continuous flow chamber where test nuclei are injected into a carrier air stream, additional care must be taken to account for the transition from turbulent to laminar flow of the carrier air. Here we present an analysis of the transient behavior and edge effects within a continuous flow parallel plate thermal diffusion cloud chamber including: (a) the transition to the steady state of the temperature field, (b) the transition to the steady state of the water vapor density field, (c) the evolution of the boundary layer along the edge of the chamber and (d) the development of the laminar parabolic flow profile from an initial “plug flow” state at the inlet to the chamber.
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