The asymmetric distribution of divertor plasma flows (DPF) has been investigated in different helical devices and different experimental conditions. In the Heliotron E experiments it was found that the DPF distributions were extremely inhomogeneous and there was no symmetry in the values of flow measured by symmetrically located collectors. Especially big difference was observed between flows registered by lower and upper collector arrays: up to factor 20-30 depending on operating conditions [1,2]. In the large scale fusion devices of the torsatron/heliotron type (e.g., LHD) such asymmetry can represent a real danger for the divertor collector plates to survive when subjected to the largest divertor flows. Several possible reasons responsible for such DPF asymmetry were discussed in [1,2], but no one was singled out. In the present work, in order to clear up the effects of plasma heating on the observed asymmetric DPF distribution, we focus on the difference of the DPF distributions between the plasma heating phase (an active stage of ECH, NBI or NBI+ECH) and the “afterglow” phase for different experimental conditions of Heliotron E, (different directions and intensities of the confining magnetic field, different heating schemes, before and after pellet injection).
         In the afterglow phase, (i) the plasma is in the regime of Pfirsch-Schlüter diffusion and effects connected with locally trapped particles would not play a role in plasma losses, (ii) the inhomogeneity connected with the locality of heating power introduced into the vacuum chamber would disappear and all plasma parameters should be constant along the torus. Therefore, the asymmetry of DPF distribution observed at this phase should be attributed to the “geometrical” reasons. The recent analysis of DPF distributions in Heliotron E for different experimental conditions demonstrated the quite strong asymmetry even for the afterglow plasma: the total flows upward (θ=π/2) and downward (θ=3π/2) to symmetrically disposed collector arrays differed 5-7 times practically independently on direction of confining magnetic field. Comparing differences of the DPF distributions for the plasma heating phase with that for the afterglow phase, the effects of the plasma heating was become clear. The following conclusions are drawn from the analysis based on this approach:
         1. The main reason of asymmetry change at the active stages of discharge, compare to that observed for the decaying plasma, is the presence of trapped particles, and the effects of locally trapped particles in a hot-electron (ECH) plasma or hot-ion (NBI) plasma reveal differently on the DPF distribution.
         2. This effect is not direct, i.e., not due to arrival to collectors of all trapped particles that drift across the confining magnetic field and leave the plasma confinement volume. The trapped particles would influence on the DPF distribution mainly through inhomogeneity of distributions of quasi-stationary electrical fields generated when trapped particles come out off the last closed flux surface.
         

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