“The required technological and safety standards for future Gen-IV Reactors can only be achieved if advanced simulation capabilities become available, which combine high performance computing with the necessary level of modeling detail and high accuracy of predictions. Interaction between different numerical codes working on various scales (DNS, RaNS, solid/structure interaction) on different parts of multiphase three-dimensional transient problem (such as nuclear reactor accident scenario) gives the ability to develop new multiscale multi-field models and simulations in various areas of nuclear engineering.”