Investigations on coolant boiling in research reactors. 1

To prepare boiling experiments in the Rossendorf research reactor WWR-SM, an experimental facility has been constructed within which, according to the conditions existing in a research reactor, coolant flow and bubble buoyancy are opposite in direction. The effects of various reactor operating parameters on the begin of boiling and departure from nucleate boiling have been studied for a single coolant channel as well as parallel coolant channels. With this, subcooled boiling characteristics have been determined which are useful for the boiling experiments to be performed in the research reactor. (author)