Abstract. Non-local heat transport experiments were performed in Alcator C-Mod Ohmic L-mode plasmas by inducing edge cooling with laser blow-off impurity (CaF 2 ) injection. The non-local effect, a cooling of the edge electron temperature with a rapid rise of the central electron temperature, which contradicts the assumption of "local" transport, was observed in low collisionality linear Ohmic confinement (LOC) regime plasmas. Transport analysis shows this phenomenon can be explained either by a fast drop of the core diffusivity, or the sudden appearance of a heat pinch. In high collisionality saturated Ohmic confinement (SOC) regime plasmas, the thermal transport becomes local: the central electron temperature drops on the energy confinement time scale in response to the edge cooling. Measurements from a high resolution imaging x-ray spectrometer show that the ion temperature has a similar behavior as the electron temperature in response to edge cooling, and that the transition density of non-locality correlates with the rotation reversal critical density. This connection may indicate the possible connection between thermal and momentum transport, which is also linked to a transition in turbulence dominance between trapped electron modes (TEMs) and ion temperature gradient (ITG) modes. Experiments with repetitive cold pulses in one discharge were also performed to allow Fourier analysis and to provide details of cold front propagation. These modulation experiments showed in LOC plasmas that the electron thermal transport is not purely diffusive, while in SOC the electron thermal transport is more diffusive like. Linear gyrokinetic simulations suggest the turbulence outside r/a=0.75 changes from TEM dominance in LOC plasmas to ITG mode dominance in SOC plasmas.
Non-local Heat Transport in Alcator C-Mod Ohmic L-Mode Plasmas2
This report discusses the different options for coupling thermal energy storage (TES) systems to advanced nuclear power plants (A-NPPs) in order to enable flexible and hybrid plant operation. An advanced light-water reactor (A-LWR), a high-temperature gas-cooled reactor (HTGR) and a liquid-metal fast reactor (LMFR) were selected as the initial use cases for demonstrating a thermally balanced energy storage coupling design for thermal power extraction. v
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.