Arturo Ocampo Ramírez

Evaluation of the Structural Integrity of the Jet Pumps of a Boiling Water Reactor under Hydrodynamic Loading

The structural integrity of a jet pump assembly of a boiling water reactor (BWR) under hydrodynamic loading was evaluated. This arrangement, which has a riser joined with a couple of jet pumps by the transition piece, is part of the reactor recirculation system. It is submerged in water under pressure. The main function is to induce forced flow through the core of the reactor. A dynamic structural analysis was carried out with the finite element method. The first ten modes of vibration and their natural frequencies were calculated. The first five natural frequencies are in the range between 25 Hz and 40 Hz. In this analysis, it was considered that the jet pump assembly is supported at the riser brace. The restrainer bracket keeps together the riser with the two jet pumps and there is free movement at the slip joints.