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Wecompare dynamical heterogeneities in equilibrated supercooledliquids and in the nonequilibrium glassy state within the frameworkof the random first order transition theory. Fluctuating mobilitygeneration and transport in the glass are treated by numerically solvingstochastic continuum equations for mobility and fictive temperaturefields that arise from an extended mode coupling theory containingactivated events. Fluctuating spatiotemporal structures in aging andrejuvenating glasses lead to dynamical heterogeneity in glasses withcharacteristics distinct from those found in the equilibrium supercooledliquid. The non-Gaussian distribution of activation free energies,the stretching exponent β, and the growth of characteristiclengths are studied along with the four-point dynamical correlationfunction. Asymmetric thermodynamic responses upon heating and coolingare predicted to be the result of the heterogeneity and the out-of-equilibriumbehavior of glasses below Tg. Our numericalresults agree with experimental calorimetry. We numerically confirmthe prediction of Lubchenko and Wolynes in the glass that the dynamicalheterogeneity can lead to noticeably bimodal distributions of localfictive temperatures during some histories of preparation which explainsin a unified way recent experimental observations that have been interpretedas coming from there being two distinct equilibration mechanisms inglasses. [ABSTRACT FROM AUTHOR]

We report results of benchmarking of core particle transport simulations by a collection of codes widely used in transport modelling of tokamak plasmas. Our analysis includes formulation of transport equations, difference between electron and ion solvers, comparison of modules of the pellet and edge gas fuelling on the ITER baseline scenario. During the first phase of benchmarking we address the particle transport effects in the stationary phase. Firstly, simulations are performed with identical sources, sinks, transport coefficients, and boundary conditions prescribed in the flattop H-mode phase. The transformation of ion particle transport equations is introduced so to directly compare their results to electron transport solvers. Secondly, the pellet fuelling models are benchmarked in various conditions to evaluate the dependency of the pellet deposition on the pellet volume, injection side, pedestal, and separatrix parameters. Thirdly, edge gas fuelling is benchmarked to assess sensitivities of source profile predictions to uncertainties in plasma conditions and detailed model assumptions. At the second phase, we address particle transport effects in the time-evolving plasma including the current ramp-up to the ramp-down phase. The ion and the electron solvers are benchmarked together. Differences between the simulation results of the solvers are investigated in terms of equilibrium, grid resolution, radial coordinate, radial grid distribution, and plasma volume evolution term. We found that the selection of the radial coordinate can yield prominent differences between the solvers mainly due to differences in the edge grid distribution. The simulations reveal that electron and ion solvers predict noticeably different density peaking for the same diffusion and pinch velocity while with the peaked profile of helium, expected in fusion reactors. The fuelling benchmarking shows that gas puffing is not efficient for core fuelling in H-modes and density control should be done by the high field side pellet injection in contrast to present machines. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]