Rectangular Hypervapotron beam-stopping elements made from Cu-Cr-Zr have been used in the Joint European Torus (JET) beam injectors to dissipate up to 100 MW of power. Experience over more than 10 yr is outstanding with not a single failure. At the flow velocities used in the Hypervapotron elements of the JET injectors, the turbulence created by the fins dominates the heat transfer, and the Hypervapotron mechanism is of secondary importance. The main advantage of the Hypervapotron is the geometrical flexibility. The surface can be shaped freely as required without compromising on either heat transfer or total power-handling capability. Flow velocity and flow rate can be independently adjusted to requirements. Peak power densities up to 30 MW/m2 were removed at a flow velocity of 7 m/s and a pressure drop of 0.25 MPa/m. Flow parameters were as follows: velocity ≤11 m/s, inlet pressure ≤1 MPa, and inlet temperature ≤50°C.
