Core plasma performance predictions with coupled core–pedestal integrated modeling for CFEDR H-mode pulse operation

Recently, the physics design of the China Fusion Engineering Demo Reactor (CFEDR) has begun, which features a larger size and takes into account multiple scenarios ranging from conservative to advanced based on the China Fusion Engineering Test Reactor (CFETR). For the first phase being reported in this paper, a 0-dimensional prediction has identified a design target for the conventional H-mode pulse operation scenario, featuring a plasma current of 15 MA and a fusion power of 1.5 GW. This study utilizes physics-based integrated modeling to evaluate the plasma performance self-consistently for the CFEDR conventional H-mode operation. It incorporates core transport, pedestal prediction, auxiliary heating, current drive, and current and equilibrium evolution modules. The quasilinear turbulent transport code TGLF employs the turbulent saturation rule SAT1 to yield robustly convergent results. The simulation results achieve the design targets of 15 MA, 1.5 GW, and the fusion gain Q=14.9 under high-density conditions, which is consistent with the expectation of the 0-dimensional prediction. The minimum safety factor is maintained above 1 by implementing reversed electron cyclotron current drive on the magnetic axis to prevent sawtooth instability. The comparison of different saturation rules shows that the simulation using TGLF-SAT1 yields the most conservative prediction on fusion power. Based on these results, the impacts of pedestal density and separatrix density on fusion power are evaluated. With a fixed pedestal density, lowering the separatrix density typically results in a lower fusion power. It is demonstrated that the influence of the broadening of alpha heating profiles due to the finite orbit width of alpha particles on plasma performance is relatively weak.