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A set of dedicated H-mode discharges with constant heating power combining Neutral Beam Injection and Electron Cyclotron Resonance Heating have been executed at the ASDEX Upgrade tokamak using a high triangularity magnetic geometry in order to investigate the impact of filamentary transport to divertor and non-divertor components. The evolution of upstream scrape-off layer (SOL) profiles have been correlated with dedicated separatrix quantities, mostly with the turbulence control parameter $\alpha_{\mathrm{t}}$ (Eich and Manz 2021 Nucl. Fusion 61 086016) describing the turbulence level at the separatrix. With increasing $\alpha_{\mathrm{t}}$ , a broadening of the upstream density profiles in the near-SOL together with the formation of a density shoulder in the far-SOL have been observed. This phenomenon is associated with an enhanced filamentary transport dominating the radial turbulent transport in the far-SOL and confirmed by means of the cooling water calorimetry on non-divertor components. The probe measurements conducted with the ball-pen probe-head mounted on the midplane manipulator and a retarding-field analyzer close to the limiter surface indicate that the key mechanism increasing the radial filamentary transport to the first wall is an increase of the particle flux $\Gamma_\mathrm{r,fil}$ , caused primarily by the packing fraction $f_\mathrm{PF, fil}$ and the filament density $n_\mathrm{e,fil}$ . At the same time, the electron temperature $T_\mathrm{e}$ and ion temperature $T_\mathrm{i}$ measured close to the limiter surface show only small variations above $\alpha_\mathrm{t}$ > 0.5. Both the filamentary heat flux and the gross erosion derived from the first wall probe measurements reach a magnitude that should be considered in the design of future fusion reactors.

A set of dedicated shots with constant heating power combining NBI (Neutral Beam Injection) and ECRH (Electron Cyclotron Resonance Heating) have been executed at the ASDEX Upgrade (AUG) tokamak using a highly shaped small ELM magnetic geometry in order to investigate the differences on heat loads at the first wall of AUG by means of the revised cooling water calorimetry. The flattop fuelling has been varied on a shot-to-shot basis while keeping constant all the other parameters, exploring a large range of the density operational space of AUG. Reducing the fuelling rate allows a gradual transition from small ELM regime at high density into a Type-I ELMy H-mode. Additionally, the safety factor q has been increased/decreased by changing Btor, which leads also to variations in the heating scheme. With the lowest flattop fuelling, reaching a Type-I ELMy H-mode, a fraction of ∼ 6% of calorimetrically captured energy loads at the first wall normalized against the entire calorimetrically captured energy has been recorded, whereas in the highest fuelling case, being in a small ELM scenario, the first wall heat loads are increased up to 16%. Considering all cases reveals an almost linear trend between the fraction of energy deposited at the first wall and the turbulence control parameter αt. This observation is consistent with an enhancement of the filamentary activity at higher αt, when the plasma turbulence is dominated by resistive interchange modes at the separatrix.