ATHLET-preCICE

Due to the use of passive safety systems in Generation 3+ reactors, the cooling circuit and the containment can no longer be considered separately. For building condensers, for example, physical effects of both systems are strongly coupled: thermohydraulics in the pipes, heat conduction in complicated three-dimensional structures (cooling fins) and a convective gas or steam flow on the outside of the condenser. The simulation of the entire system is therefore a multiphysics problem, and thus a coupling of several simulation programs is necessary. A general code-independent coupling can be realized very efficiently using the open source coupling library preCICE, which is being developed at the Chair of Scientific Computing at the Technical University of Munich and the Chair of Simulation of Large Systems at the University of Stuttgart. Within this project we want to develop a preCICE adapter for AC2. This adapter will first be implemented for the module ATHLET. Since for a large number of different simulation programs, such as ANSYS Fluent, COMSOL, OpenFOAM, CalculiX, or Code_Aster, preCICE adapters already exist, all these programs would thus be directly available for coupled analyses with ATHLET. A further advantage of coupling via preCICE is that it allows not only to couple two simulation programs simultaneously, but three or even more -- a strict requirement for a detailed simulation of the aformentioned building condensers. Since similar multiphysical problems also occur with modular reactors, which are seen in many countries as the future of nuclear technology, the intended implementation of a preCICE adapter for ATHLET is a necessary step for the future viability of ATHLET.

Funded by the BMWi: Federal Ministry for Economics Affairs and Energy

• Fabian Weyermann, Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) gGmbh
• Hans-Joachim Bungartz, Technical University of Munich