Showing papers in "International Journal of Heat and Technology in 2003"

Self pressurization behaviour in integrated reactors

Abstract: This paper describes the transient performance of an integral self-pressurized reactor system, when a partial reduction in the SG removal power, without control or safety actions, is assumed. CAREM reactor is taken as a reference. The thermalhydraulic system code RELAP has been used for the analysis. A special effort has been done in order to model 3-D flow paths by a 1-D code, specially within the reactor dome, that constitutes a large volume where flow paths are not well-defined. A detailed nodalization is developed, in order to allow the movement of the fluid and “fictitiously” reproduce fluid movements because of natural convection and thermal losses. Also a simpler nodalization, with a unique hydraulic node to simulate the reactor dome, is used. A parametric study is performed in order to analyze dependence of pressure evolution with relevant factors that govern the dome dynamic behavior, regarding steam condensation on structures. The results obtained with both nodalizations are compared. An important feedback of the whole primary system on the pressure evolution has been characterized from the performed analysis.