New concept for the vessel of a nuclear power reactor with supercritical coolant parameters

A multiwall design, akin to a Russian nested doll, of a nuclear reactor vessel is described. This design is intended for reactors with supercritical coolant parameters. The interwall gaps of a multiwall vessel are hydraulically connected with the reactor coolant via a separative device. A system of pressure regulators distributes the coolant pressure successively over the gaps in a manner so that in the operating regime a wall would be under the optimal nominal stress. To eliminate any danger of the vessel collapsing in the event that the counter pressure system malfunctions, ribbed rings with axial channels are tightly installed in the gaps between the walls. This makes it possible to freely fill the gaps in the vessel with a working body, for example, water. In the event that the counterpressure system fails the multiwall vessel is automatically converted into a multilayer wall, which eliminates the possibility of the vessel being destroyed. To increase the reliability of such a vessel, one or two additional walls, which can carry a load, for example, at the end of operation when the inner walls, which are subjected to the highest neutron irradiation, partially lose their strength, are installed in the vessel. Translated from Atomnaya énergiya, Vol. 105, No. 6, pp. 322–325, December, 2008.