3 results about "Fuel cycle" patented technology

This invention provides a method, system, device, and medium for assessing the availability of a neutron detector, relating to the field of commissioning and maintenance technology for external nuclear instrumentation systems in nuclear power plants. The assessment method includes: obtaining the high-pressure characteristic curve of the neutron detector for the current fuel cycle; obtaining the plateau slope of the neutron detector for the current fuel cycle based on the high-pressure characteristic curve; obtaining the voltage margin of the high-pressure characteristic curve of the neutron detector for the current fuel cycle based on the high-pressure characteristic curve, the current power level of the reactor, the upper limit of the power level to be measured by the neutron detector, the operating voltage of the neutron detector, and the upper limit of the low-pressure region voltage of the neutron detector; and determining the availability of the neutron detector based on the plateau slope and the voltage margin of the high-pressure characteristic curve. The assessment method, system, device, and medium provided by this invention can comprehensively assess the current availability of the neutron detector and predict its remaining service life without changing the external nuclear instrumentation system equipment.

This invention discloses a simulation method for differential refueling in a pebble bed reactor based on a semi-Lagrange fixed-grid backtracking algorithm, relating to the field of fuel cycle calculation technology for high-temperature gas-cooled reactors. The method includes: calculating the macroscopic burnup depth and poison nucleus density of fuel spheres in each grid of a homogenized pebble bed using a core diffusion program; calculating the backtracking distance of each grid based on the flow velocity in the channel where each grid is located and the time step used in each refueling step, and determining the position before backtracking; calculating weighting coefficients based on this backtracking position, and updating the macroscopic burnup depth and poison nucleus density of fuel spheres in the calculation grid using a cubic spline interpolation function; and finally correcting the calculated macroscopic burnup depth and poison nucleus density using a correction equation. This invention solves the numerical dispersion and oscillation problems existing in traditional methods, significantly improving the smoothness and stability of core physics field calculations under differential refueling conditions.

A self-contained, offshore, underwater nuclear power plant is housed within a hull mounted to the seafloor. An electric line extends from the offshore power plant to an onshore electric load to power the electric load. The body of water provides a heat sink for the power plant, and protection from surface weather, waves, and currents. The hull mounts to the seafloor via a dampener that reduces the transfer of seismic activity from the seafloor to the hull. The hull and power plant may be manufactured at an onshore facility and transported to an offshore location of operation on the seafloor. After completion of a fuel cycle, the hull and power plant may be transported from the offshore location of operation to an onshore maintenance / refueling facility for refueling, repair and later, when obsolete or damaged, for decommissioning.