HIGH PERFORMANCE COMPUTATION AND WALKTHROUGH VISUALIZATION FOR ASSESSING SEISMIC SAFETY OF NUCLEAR POWER PLANTS

摘要

We have been developing a multi-scale and multi-physics based numerical simulator for quantitatively predicting actual quake-proof capability of ageing NPPs under operation or just after plant trip subjected to strong earthquake. Here we divide the whole phenomena into three sub-phenomena, and develop simulation codes and numerical models for the sub-phenomena. As for a main sub-phenomenon, we construct full scale and precise 3D finite element models of building, pressure vessels with internal structures with nearly billion degrees of freedom, and perform dynamic nonlinear response analyses with considering fluid-structure interaction between pressure vessel, internal structures and coolant by iterative partitioned coupling algorithms. We also develop a parallelized walkthrough visualization technique to effectively deal with a huge amount of data coming from large scale dynamic simulations. Those simulation codes are now being tuned for Japanese Peta-flops computer "K" with sub-millions cores. In this paper, we describe key algorithms of the simulation methods and some preliminary results.