ITER is envisioned to operate in two phases: the Physics Phase, ∼ 6 yrs, is devoted to the physics issues followed by the Technology Phase, ∼ 8 yrs, used mainly for technology testing. The nuclear testing program of ITER is intended to provide powerful, albeit partial, demonstration of the ultimate potential of a fusion blanket. The ITER test group, which consists of a number of ITER designers and experts from the home teams concerned with the long-term development of fusion technology, has carried out several tasks, including: 1) Definition of the testing requirements on the major parameters of ITER; 2) Definition of the test program (time-space matrix and priorities of tests); 3) Engineering design of test modules; 4) Ancillary equipment to support test module operation and 5) Allocation of available test space among countries. Recommended ITER parameters are: neutron wall load ∼ 1 MW/M2, lifetime neutron fluence ∼ 3 MW y/m2 and several periods of continuous operation (∼ 100% availability with back to back pulses or steady state) of ∼ 1 to 2 weeks each. The requirements on plasma burn and dwell times are quantified. Steady state operation is a desirable goal. If this goal cannot be achieved, a burn time of ∼ 1 to 3 hours, depending on the breeder temperature, is needed for tritium release tests in solid breeders. The requirements for ancillary equipment outside the torus, required to support the test modules (e.g., heat rejection systems, tritium processing, etc.) are extensive and they substantially influence the overall design engineering. The space available for testing in ITER is not sufficient for 4 complete programs (one for each country). An effective strategy for allocation of test ports among countries is being evolved. It involves a combination of collaboration on some tests, and allocation of testing space and time by party.
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