Published 4 issues per year
ISSN Print: 0276-1459
ISSN Online: 1943-6181
Indexed in
EXPERIMENTAL STUDY ON STABILITY OF STARTUP IN NATURAL CIRCULATION BWRS WITH AND WITHOUT NUCLEAR COUPLING
ABSTRACT
Several experiments have been performed in Purdue University Multi-Dimensional Integral Test Assembly (PUMA) facility to study the startup transient in a natural circulation BWR design. The strategy for the experimental study has been developed from pressure scaling based on single- and two-phase flow scaling laws. In the experiments, the differences of the stored energy of the solid structures and the core inlet subcooling between the facility and a natural circulation BWR design have been taken into account. A novel core inlet plate has been designed and installed to study the effect of the core inlet flow-loss coefficient on the startup instabilities, namely geysering and flashing-induced loop type oscillations. The experiments for the startup transient have been performed with and without considering the void-reactivity feedback. Based on a detailed analysis for the fuel heat conduction dynamics and neutron kinetics, the scaling criteria for the void-reactivity feedback simulation have been derived. By means of the local void fraction measurements with conductivity probes installed in the core section of the PUMA reactor pressure vessel, the void-reactivity feedback has been studied through the real-time solution of the point kinetic model equations. The presence of the void-reactivity coupling has been found to have a major destabilizing effect especially for the flashing-induced loop type oscillations.
-
Lee Jin-Der, Lin Yuh-Ger, Chen Shao-Wen, Pan Chin, The influence of void-reactivity feedback on the bifurcation phenomena and nonlinear characteristics of a single nuclear-coupled boiling channel, Annals of Nuclear Energy, 94, 2016. Crossref