Method for determination of water hammer conditions and consequences in pressurizers of nuclear reactors

Abstract

Results of known experimental and computed studies of conditions for water hammers (WHs) in reactor pressurizers are analyzed. It is found that when emergency opening of pilot-operated safety valves of the pressurizers of nuclear reactors happens, WHs can be generated on pressurizer elements, and amplitudes of hydrodynamic load pulses significantly override the limiting values. An original method for determination of the WH conditions and consequences in the case of emergency filling of the pressurizers of nuclear reactors is proposed. Unlike the traditional Joukowski formula, the presented method considers the key features and effects of the WH conditions and consequences in the pressurizers of nuclear reactors. The results of computer modeling of the maximum amplitudes of a pressure pulse of WHs using the presented method are in satisfactory agreement with Korolyev’s experiments on the pressurizer model of nuclear reactor. The proposed method is universal for all types of water-cooled nuclear reactors (including the Akkuyu reactor plants). Variation calculations using the presented method have found that a considerable increase in total hydraulic resistance of internal elements can be an effective action to prevent WHs in the pressurizers of nuclear reactors.