Abstract
In case of strong earthquakes, control rods are set in gaps between fuel assemblies to scram nuclear reactors. In seismic design of nuclear reactors, predicting the behavior of control rod insertion during earthquakes is important for estimating the scrammability. We developed a numerical analysis model for the scrammability of boiling water reactor. This model consists mostly of beam elements and lumped mass elements. We compared our calculations with the results of experiments using our proposed model. With the results of our analysis, we came to the following conclusions. First, our proposed model can simulate the behavior of control rod insertion such as the time history of control rod velocity and contact drag. Also, our proposed model provides good agreement with scram time.
