Core-Edge Integrated Predictive Studies of ST40 Plasmas in Preparation for FPP Design

The dynamic interplay between the core and edge plasmas have significant impact on various aspects of a reactor scenario design. The transport of the SOL plasma determines the plasma conditions at the separatrix, which poses boundary conditions for core transport. The plasma edge also impacts myriad particle transport processes, which has implications on core plasma fueling, impurity transport, as well as divertor survivability. A core-edge integrated approach is therefore necessary to produce plasma scenarios that are consistent with both core and edge transport. A reduced model for the SOL, the so-called SOL Box Model, has been previously developed to calculate upstream conditions based on core to edge transport in a time-dependent simulation, and applied to analysis of NSTX-U plasmas with TRANSP. Here we present predictive studies of ST40 plasmas with separatrix boundary conditions provided by the SOL Box Model, under various operation regimes. Free parameters of the SOL model will be constrained with time-slice simulations of the plasma boundary done with high fidelity modeling. The predictions will be compared with existing ST40 discharges to evaluate the validity of the methodology. Implications for FPP conceptual designs will be discussed.