Investigation of wall loadings arising due to steam condensation in the pressure suppression system of boiling water reactors

A theoretical study of bubble collapse under idealized conditions (infinite incompressible fluid) provides some fundamental results about the pressure variations generated around the bubble. The pressure behavior occurring during vapor bubble collapse in condensation experiments can be explained empirically by means of a simple power series formula for the bubble radius, so that the measured values of pressure development enable conclusions to be made for the approximate initial bubble size. A simple model shows for very short-term pressure pulses the limiting influence exerted by the compressibility of water on the pressure amplitudes. Using a simplified coupled fluid-structure model, it is shown that these short-term pressure pulses cause only tolerable local bending stresses in the wall of the pressure suppression system