This study investigates the plasma performance in HT-6 M tokamak using 1.5D integrated predictive modeling code BALDUR. The simulations are carried out under the designed plasma conditions, including R = 65 cm, a = 20 cm, B T = 1.5 T, n e = 1 × 10 19 m −3 and I p = 40-150 kA without external heating. In these simulations, a combination of turbulence and neoclassical transports is used for predicting thermal and particle transport. Thus, the plasma evolution for plasma current, temperature, and density can be predicted under a designed condition. In addition, the influence of current rampup for the plasma performanceis investigated. The scenario study for the tokamak is also carried out by varying plasma current. To summarize the results yield the electron temperature at the center T e (0) = 477-1,551 eV (MMM95) and 328-1,384 eV (Mixed B/gB), the ion temperature at the center T i (0) = 26-50 eV (MMM95) and 18-42 eV (Mixed B/gB) the electron densit y = 6.4 × 10 18-1.4 × 10 19 m −3 in both Mixed B/gB and MMM95 simulations. Using the obtained plasma parameters, the radiated power of the carbon impurity is assessed.

Self-consistent simulations of four DEMO designs proposed by teams from China, Europe, India, and Korea are carried out using the BALDUR integrated predictive modeling code in which theory-based models are used, for both core transport and boundary conditions. In these simulations, a combination of the NCLASS neoclassical transport and multimode (MMM95) anomalous transport model is used to compute a core transport. The boundary is taken to be at the top of the pedestal, where the pedestal values are described using a pedestal temperature model based on a combination of magnetic and flow shear stabilization, pedestal width scaling and an infinite- n ballooning pressure gradient model and a pedestal density model based on a line average density. Even though an optimistic scenario is considered, the simulation results suggest that, with the exclusion of ELMs, the fusion gain Q obtained for these reactors is pessimistic compared to their original designs, i.e. 52% for the Chinese design, 63% for the European design, 22% for the Korean design, and 26% for the Indian design. In addition, the predicted bootstrap current fractions are also found to be lower than their original designs, as fractions of their original designs, i.e. 0.49 (China), 0.66 (Europe), and 0.58 (India). Furthermore, in relation to sensitivity, it is found that increasing values of the auxiliary heating power and the electron line average density from their design values yield an enhancement of fusion performance. In addition, inclusion of sawtooth oscillation effects demonstrate positive impacts on the plasma and fusion performance in European, Indian and Korean DEMOs, but degrade the performance in the Chinese DEMO.

Thailand Institute of Nuclear Technology (TINT) is planning to develop Thailand Tokamak I from HT-6 M tokamak. In the first phase of operation, the device will be equipped with two fueling systems: gas puffing (GP) and supersonic molecular beam injection (SMBI). Since the SMBI system has never been used experimentally with this device, this work, therefore, numerically studies the penetration features of SMBI in the plasma of Thailand Tokamak I, based on the nominal parameters of HT-6 M tokamak. The interaction of the supersonic molecules with the plasma has been computed by BOUT++ code which solves six-field fluid model of SMBI model in the radial direction. The preliminary results demonstrate that the SMBI is an efficient method for fueling the plasma and the beam can be delivered to the center of the plasma core.

Simulations of future Thailand tokamak plasmas are carried out using a CRONOS integrated predictive modelling code. The design of the reactor is based on nominal parameters of HT-6 M tokamak. The code consists of a 1D transport solver with general 2D magnetic equilibria, and includes several heat, particle and impurities transport models as well as heat, particle and momentum sources. In this work, a combination of a mixed Bohm/gyro-Bohm anomalous transport model and an NCLASS neoclassical transport model are used to calculate plasma core diffusivities. The boundary condition of the simulations is taken to be at the top of the pedestal which is calculated based on an international multi-tokamak scaling. Sensitivity analyses on plasma performance of the future Thailand tokamak are investigated by varying plasma current, toroidal magnetic field and external heating schemes. It is found that the performance in H-mode plasmas such as transport barrier at plasma edge and central temperatures are found to be sensitive to heating schemes and their magnitudes. Additionally, ICRH and LH methods appear to be the most effective scheme of heating for ion and electron temperatures, respectively. Central ion temperature in the range of 120-750 eV and central electron temperature in the range of 1,100-2,750 eV with heating are expected.

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