Nuclear fusion technology is projected to play a major role as a source of clean and safe energy in the future. The immediate challenge is to develop sustainable fusion reactors. In the process of converting complex physical theories to working engineering applications, modelling and simulation assumes a vital position. While simulating nuclear fusion devices, the physical and geometrical complexity arising from different scales and physical regimes needs to be addressed. Specifically for tokamak devices, the regimes are broadly classified into core and edge regions. Simulating both regions in a single software is a laborious task and mostly segregated analysis is pursued. The edge and core regions can be coupled in a way that the individual analysis remains the same and some form of data communication across a physical boundary takes place. To perform this coupling, a partitioned black-box approach is pursued using the open-source coupling library preCICE. A model diffusion problem is simulated in the edge physics code GRILLIX having a Cartesian grid and a core physics code having a polar coordinate system. The edge region is simulated by the GRILLIX code and the core region is simulated by a custom-built code as a part of this thesis. A coupling in which the core is modelled with a polar coordinate system and the edge with a Cartesian grid is shown to be first order convergent. Global and local Radial-basis function mapping schemes available in preCICE are tested. A comparative analysis of mapping entities within GRILLIX and doing the same operation with preCICE is shown. In the last part, a strategy for coupling with diverted geometries in cylindrical and curvilinear coordinate systems is presented.     «

Nuclear fusion technology is projected to play a major role as a source of clean and safe energy in the future. The immediate challenge is to develop sustainable fusion reactors. In the process of converting complex physical theories to working engineering applications, modelling and simulation assumes a vital position. While simulating nuclear fusion devices, the physical and geometrical complexity arising from different scales and physical regimes needs to be addressed. Specifically for tokama...     »