A high performance water-cooled thermal shield device

The shielding of the heat flux coming from plasma is one of the most limiting factors in plasma-facing component (PFC) design. In fact, the performance of a cooled divertor plate system is mainly limited by the heat transfer capability (maximum value of the critical heat flux CHF) and by the capability to sustain thermal stresses, even if the maximum allowable heat flux is determined by the thermal conductivity of the protective material (maximum temperature value on the plasma facing surface). A new concept for cooled thermal shield design was devised and tested. Analyses and tests demonstrate that the new concept introduces very high improvement in PFC design, in terms of both heat removal capability (very high CHF) and related stress performance. Up to 80 MW/m/sup 2/ under steady state were successfully applied.