Parallel convection and E × B drifts in the TCV snowflake divertor and their effects on target heat-fluxes
Parallel convection and E × B drifts act together to redistribute heat between the strike-points mechanisms is enhanced near the secondary X-point and is shown to dominate over heat in the low field side snowflake minus (LFS SF−). The cumulative heat convection from both conduction, partly explaining why the LFS SF− distributes power more evenly than the single null (SN) or other snowflake (SF) configurations. Pressure profiles at the entrance of the divertor are strongly affected by the position of the secondary X-point and magnetic field between the outer-midplane (OMP) and the divertor entrance enhancing the role of parallel direction indicating the importance of E × B drifts. Pressure drops of up to 50% appear heat convection. The electron temperature and density profiles and the radial turbulent fluxes measured at the OMP are largely unaffected by the changes in divertor geometry, even on flux surfaces where the connection length is infinite.
Tsui_2021_Nucl._Fusion_61_046004.pdf
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Snowflake Review 2021-01-04.pdf
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