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G7 pledges support for nuclear at Italy meeting
The Group of Seven (G7) recommitted its support for nuclear energy in the countries that opt to use it at a Ministerial Meeting on Climate in Italy last month.
In a statement following the April meeting, the group committed to support multilateral efforts to strengthen the resilience of nuclear supply chains, referencing the goal set by 25 countries during last year’s COP28 climate conference in Dubai to triple global nuclear generating capacity by 2050.
J. L. Kloosterman, V. V. Golovko, H. van Dam, T. H. J. J. van der Hagen
Nuclear Science and Engineering | Volume 139 | Number 2 | October 2001 | Pages 118-137
Technical Paper | doi.org/10.13182/NSE01-A2227
Articles are hosted by Taylor and Francis Online.
A new type of nuclear reactor is presented that consists of a graphite-walled tube partly filled with TRISO-coated fuel particles. Helium is used as a coolant that flows from bottom to top through the tube, thereby fluidizing the particle bed. Only when the coolant flow is large enough does the reactor become critical because of the surrounding graphite that moderates and reflects the neutrons.The fuel particle designed for this reactor is strongly undermoderated and has a temperature coefficient of reactivity that is sufficiently negative. The outer diameter is 1 mm with a fuel kernel diameter of 0.26 mm. The fuel enrichment (16.7%) and the core inventory (120 kg of uranium) inherently limit the maximum power to 16 MW(thermal).A lumped-temperature point-kinetics model has been made that describes the fluidization of the particle bed, coupled to the thermal hydraulics and the neutronics of the core. The model has been linearized around the stationary solution, and the transfer function from coolant mass flow rate perturbations to reactor power fluctuations has been calculated. From a root-locus analysis, the reactor operation is shown to be stable with respect to small variations of the coolant mass flow rate around the stationary operation points.Transient analyses with the nonlinear reactor model show that for the three transients considered (a step in the coolant mass flow rate, a decrease of the coolant inlet temperature, and a loss of heat sink), the fuel temperature remains well below 1600°C. Recommendations are made for further research.