A study of the dynamics of SECURE reactors: Comparison of experiments and computations

• Published in: Nuclear engineering and design 1990-09, Vol.122 (1), p.387-399
• Main Authors: Babala, Dušan, Bredolt, Ulf, Kemppainen, John
• Format: Article
• Language: English
• ISSN: 0029-5493; 1872-759X
• DOI: 10.1016/0029-5493(90)90222-J

Pressurized Water Reactors designed according to the PIUS principle possess unique characteristics that make their safety independent of the usual multitude of engineered safety systems, and virtually immune to human error during operation. A basic feature of this principle is the self-protective thermo-hydraulics of the primary system that prevents core power from exceeding the cooling capability of the submerging water, independently of outside surveillance and intervention. This paper describes the experimental demonstration of the self-protective features of the primary system in a large scale test loop in ABB Atom's engineering laboratories. The loop employs real time simulation of core power as a function of coolant conditions in an electrically heated mock-up of a fuel assembly. System responses to disturbances of various types and severity were studied. Comparisons were made with predictions by the RIGEL code, which has been developed specifically for the study of PIUS-type reactors. Selected results are presented in this paper. The tests have demonstrated the self-protective thermo-hydraulics of the primary systems of Pressurized Water Reactors designed according to the PIUS principle, and verified the capability of the RIGEL code to predict the dynamics of such systems.