IMAS-ification of TRANSP: generalization of interfaces to data and physics modules

The TRANSP code [https://doi.org/10.11578/dc.20180627.4] is an interpretive and predictive modeling code for tokamak plasmas. It is widely used around the world for analysis of experimental data, model validation, and tokamak scenario development. State-of-the-art equilibrium solvers, models for heating and transport are used in the code. Traditionally, the implementation of such physics modules requires development of module-specific interfaces that take into account the grid requirements, unit conversions, and individual numerical parameters for each physics component. In this paper, we report progress in the implementation of a new coupling approach that is based on the ITER Integrated Modeling & Analysis Suite (IMAS). The IMAS interface prescribes units, defines grids, and sets standards on saving the numerical parameters for individual physics components. It also specifies a uniform approach in accessing experimental data and saving modeling results in the IMAS databases. An option to initialize TRANSP from an IMAS database and to save output directly to IMAS has been recently added to TRANSP so that TRANSP can be used as an IMAS actor on the networks that utilize the IMAS infrastructure. The coupling to heating and current drive modules such as TORBEAM for ECH is used to demonstrate the new coupling scheme. This new approach simplifies the coupling of new physics modules to TRANSP. Here, we also discuss challenges towards complete IMAS-ification of the TRANSP code.