The DTT facility will test the physics and technology of various alternative divertor concepts under conditions that can confidently be extrapolated to DEMO. This derives from the need to develop integrated, controllable exhaust solutions for DEMO including plasma, PFCs, control diagnostics and actuators, using experiments, theory and modelling. The specific objectives are to:

  • demonstrate a heat exhaust system capable of withstanding the large load of DEMO in case of inadequate radiated power fraction.
  • close the gaps in the exhaust area that cannot be addressed by present devices.
  • demonstrate that the possible (alternative or complementary) solutions (e.g., advanced divertor configurations or liquid metals) can be integrated in a DEMO device, e.g. via demonstration that:
    • a closed loop liquid metal heat removal system is viable in a tokamak despite hydride formation at relevant edge and SOL parameters;
    • liquid metals are applicable to DEMO (impurities, MHD, etc.);
    • an integrated exhaust scenario is viable;
    • divertor operation is possible with edge parameters ν*,ρ' & n/nGW in the range of ITER/DEMO (taking also account of high core radiation fraction in DEMO).