TECHNICAL FIELD

The present invention relates to a nuclear reactor, in particular a nuclear reactor formed by a number of fuel elements characterized by a support system of new conception.

STATE OF THE PRIOR ART

Under current practice, nuclear reactors include a core, positioned in the lower part of the main vessel of the reactor, immersed in the primary fluid and formed by fuel elements supported by a support grid.

Reactors using known solutions have various drawbacks.

The core support grid is usually anchored to the bottom of the reactor vessel and is difficult to inspect and difficult/impossible to replace, and so it is necessary to limit damage caused by neutron flux. To this end, each fuel element extends in length beneath the active part so as to reduce damage to the support grid.

In the particular case of using heavy liquid metals as the primary coolant, there is a serious floating effect that requires complicated anchorage of the fuel elements to their support grid and/or balancing with the use of high-density materials, such as tungsten.

Patent application MI2008A000766 attempts to answer this problem by adopting a support structure at the top end instead of the bottom end of the fuel element, resorting to a structure with beams passing through penetrations made in the shell containing the reactor and on which they rest, and in which each beam of the support structure supports a row of fuel elements, passing through them in a slot located below the head of the element.

This solution has the limitation of only being usable with square pattern fuel elements, and has various drawbacks when the penetrations pass through the primary confining barrier and the need for two sets of sliding beams to allow detachment of the fuel element to be replaced, said sets of beams being bulky and potentially interfering with the other structures located in the upper part of the reactor.

SUBJECT OF THE INVENTION

One object of the present invention is to provide a nuclear reactor that overcomes the indicated drawbacks of known solutions and has further constructional and safety advantages.

The present invention thus relates to a nuclear reactor, as defined in the appended claim1and, for its auxiliary characteristics and plant configurations, in the dependent claims.

