Steam-cooled nuclear reactor

The steam-cooled reactor serves to generate power or to propel ships. The moderator is formed by light water, heavy water or mixtures of both. In order to improve the compact direct-cycle reactor part of the superheated steam contained in the reactor core is fed directly into a turbine or used to propel the ship. The remainder of the superheated steam is conducted into water contained in the pressure vessel; in this way saturated steam is produced. This saturated steam is again introduced into the reactor core by means of pumps in order to cool it continuously after shutdown of the reactor. For this purpose among others three different steam distributors are arranged above the reactor core. The fuel assemblies have got a central and several peripheral steam channels which are in contact with each other at the lower end of the tube-shaped fuel element. (DG)