Low-output nuclear reactor located in the cavern of a pressure vessel

摘要

The invention concerns a nuclear reactor with spherical fuel elements and low output, that is particularly suitable for generating thermal energy for heating purposes. It has a helium primary loop and a water secondary loop, which includes cooling tubes located on the inner surface of the reactor pressure vessel. The fuel elements form a stationary bed; i.e. there is no stirring or reloading. In order to prevent reactivity increasing in case of ingress of water into the core, without additional internals or active measures, it is proposed to add boron (atomic or as a compound) to the water of the secondary loop. The percentage of boron in the water can be much less than one percent.