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M. Gorelenkova

Publications and source records attributed to M. Gorelenkova.

3 recordsLinked to original sources

Non-dimensional confinement scaling in similar negative triangularity plasmas on the DIII-D and TCV tokamaks

Similarity experiments were performed on the DIII-D and TCV tokamaks to explore the scaling of energy confinement in negative triangularity plasmas using non-dimensional variables. Near up-down symmetric plasmas with large top-bottom averaged negative triangularity were created in a lower single null configuration, with the shape of the separatrix being closely matched between the two devices. The normalized energy confinement is found to weakly improve at increasing collisionality and, between the two devices, shows a machine size scaling behavior between Bohm and gyro-Bohm. Engineering scaling on a large DIII-D dataset is in agreement with the non-dimensional experiment.

physics.plasm-ph

TRANSP integrated modeling code for interpretive and predictive analysis of tokamak plasmas

This paper provides a comprehensive review of the TRANSP code, a sophisticated tool for interpretive and predictive analysis of tokamak plasmas, detailing its major capabilities and features. It describes the equations for particle, power, and momentum balance analysis, as well as the poloidal field diffusion equations. The paper outlines the spatial and time grids used in TRANSP and details the equilibrium assumptions and solvers. Various models for heating and current drive \mc{and radiation}, including updates to the NUBEAM model, are discussed. The handling of large-scale events such as sawtooth crashes and pellet injections is examined, along with the predictive capabilities for advancing plasma profiles. The integration of TRANSP with the ITER Integrated Modeling and Analysis Suite (IMAS) is highlighted, demonstrating enhanced data access and analysis capabilities. Additionally, the paper discusses best practices and continuous integration techniques to enhance TRANSP's robustness. The suite of TRANSP tools, designed for efficient data analysis and simulation, further supports the optimization of tokamak operations and coupling with other tokamak codes. Continuous development and support ensure that TRANSP remains a major code for the analysis of experimental data for controlled thermonuclear fusion, maintaining its critical role in supporting the optimization of tokamak operations and advancing fusion research.

physics.plasm-ph

The hidden uncertainties in particle balance calculations and their implications for assessment of plasma performance

Predictive simulations of mixed plasma discharges, like deuterium-tritium plasmas, rely on self-consistent models for particle transport. These models have to be validated with interpretive analysis of existing experiments. Accounting for uncertainties in the particle balance equation is important for modelling of mixed-plasma discharges because simulation results are directly affected by plasma composition. JET deuterium and mixed hydrogen-deuterium plasma discharges heated by neutral beams only are analysed with the TRANSP code. Influence of prescribed quantities and terms entering into the particle balance equation is quantitatively assessed on the computed plasma parameters, in particular on the neutron rate and the plasma energy. Large uncertainties in the prescribed ion temperature, plasma rotation and impurity content might result in a noticeable over- or underestimate of the computed neutron rate. A significant difference in the time evolution of the measured and computed neutron rate is observed in the interpretive simulations if same diffusivity for electrons and thermal ions is assumed. Increased thermal deuterium ion transport is required to reach agreement with the plasma composition measured at the plasma edge and the measured neutron rate. Thermal ion density computed with the particle balance equation is mostly affected by the ion outflux term.

physics.plasm-ph