Geometry-Aware Coupling of Multimodel Simulations and Data for Digital Twins through the Parallel Coupler for Multimodel Simulations (PCMS)

A key goal of digital twins is to develop modeling systems that can capture the lifecycle of a fusion power plant and provide a platform for online feedback and control through data feedback loops. The construction of a fusion digital twin requires stitching input data together from a variety of sources spanning the range of high-fidelity models, to surrogate models, to reactor diagnostics. A fundamental challenge is designing tools that can interface digital twin components across this span and account for unique difficulties in fusion devices such as the use of physics-based coordinate systems (like Boozer, VMEC, etc.), high dimensional data, and complex geometries. This talk describes the ongoing effort to support geometry aware high and low fidelity coupling in Tokamaks and Stellarators through the Parallel Coupler for Multimodel Simulation (PCMS). We will discuss our approach to bridge data from a range of fusion analysis codes on leadership class supercomputers including support for a range of field transfer methods, coordinate transformations, and parallel control utilities. We will also describe progress towards integration with the IMAS/OMAS schemas to support integration with experimental data.