PRELIMINARY STUDY OF PRESSURES CONTRIBUTION INSIDE A LIQUID METAL FILLED CPS AS DIVERTOR TARGET

Power exhaust problem is growing in interest as the tokamak power of the foreseen projects ITER, DTT, DEMO increases, achieve the required maturity for the employed technology to face this problem is therefore crucial. Particles escaping plasma confinement bring many consequences to deal with, from erosion of the impinging target, to plasma contamination passing through the very high heat load that needs to be dissipated in the divertor region. To find the optimal choice according to each aspect is not an easy task and a balance of the capability to face them by the different divertor solutions is under study, among these proposals a capillary porous structure (CPS) is envisioned to keep in place a thin film of liquid metal that can be exploited as a primary facing component (PFC) free from radiation damage and able to cope with higher power loads also by mean of his latent heat of evaporation. Such solution is not free of drawbacks, that have to be approached and solved, the effective confinement and replenishment of the liquid metal into the CPS by the capillary force is one of the concerns, since particles ejection may result in plasma contamination, and inefficient pumping may expose the solid capillary wick to the power exhaust that will degrade the device structure. This thesis tries to address such problem in a preliminary study of the pressures involved inside the CPS that move the liquid metal and how different design parameters tends to affect them.