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DOE selects first companies for nuclear launch pad
The Department of Energy’s Office of Nuclear Energy and the National Reactor Innovation Center have announced their first selections for the Nuclear Energy Launch Pad: three companies developing microreactors and one developing fuel supply.
The four companies—Deployable Energy, General Matter, NuCube Energy, and Radiant Industries—were selected from the initial pool of Reactor Pilot Program and Fuel Line Pilot Program applicants, the two precursor programs to the launch pad.
Emerson Paul Chivington, William E. Kastenberg
Nuclear Science and Engineering | Volume 83 | Number 3 | March 1983 | Pages 350-365
Technical Paper | doi.org/10.13182/NSE83-A17568
Articles are hosted by Taylor and Francis Online.
A technique is developed for the treatment of space-time neutron kinetics, which can include the effects of material motion. The new method is applied to sample problems where azimuthal fuel motion is postulated to occur. The technique developed employs the finite element method, Gear's variable predictor corrector scheme, and a Lagrangian mesh that moves with the reactor materials. We treat a cylindrical reactor in (r,θ) geometry. Because finite elements are used to describe both the fluxes and the boundaries of the mesh elements, the resulting deformed elements could be arbitrarily shaped. Second-order polynomials (elements) were found to be better than linear polynomials in treating the geometry because of the curved boundaries used in the problem. Azimuthal motion was found to increase reactivity, and large motion resulted in large increases in reactor power for the cases studied. However, the cases studied showed that azimuthal motion was less important than both inward and outward radial motion. Point kinetics (based on first-order perturbation theory) did not accurately predict the power excursion in cases where substantial azimuthal displacement occurred.