The invention relates to safe operation support systems of nuclear power plants (NPPs) at severe accidents, including methods and systems for cooling and cooling control of the reactors molten core. The invention increases safety of NPP and cooling efficiency of the molten core of a reactor. The invention increases the efficiency of cooling the molten core of a reactor by safely removing the heat load from the molten metal mirror, ensuring the elimination of vapor explosions. The invention changes the principle of cooling the reactor molten core, in that after the molten core destroys the reactor vessel, the conditions for subsequent cooling of the molten metal are determined by the characteristics of the trap casing, but not of the reactor.

The invention relates to safe operation support systems of nuclear power plants (NPPs) at severe accidents, including methods and systems for cooling and cooling control of the reactors molten core. The invention increases safety of NPP and cooling efficiency of the molten core of a reactor. The invention increases the efficiency of cooling the molten core of a reactor by safely removing the heat load from the molten metal mirror, ensuring the elimination of vapor explosions. The invention changes the principle of cooling the reactor molten core, in that after the molten core destroys the reactor vessel, the conditions for subsequent cooling of the molten metal are determined by the characteristics of the trap casing, but not of the reactor.

Devices, including wireless temperature sensors, are provided. The devices may include a patch including a conductive material, a substrate, and a ground plane. The devices may be used in the systems and methods provided herein to measure a temperature. The substrates of the devices may include a dielectric material or a metal.

A Control Neutron Absorber (CNA) assembly for a microreactor that produces nuclear energy is disclosed. The CNA assembly includes a housing, a CNA rod, and a burnable absorber. The housing includes an inner housing and an outer housing. The inner housing is configured to receive a CNA rod. The outer housing extends coaxially with the inner housing and is positioned radially outward and offset from the inner housing defining a cavity therebetween. The CNA rod includes a neutron absorbing rod including a first neutron absorbing material. The neutron absorbing rod is positioned within the inner housing and is configured to move axially relative to the inner housing. The burnable absorber includes a second neutron absorbing material, exhibits a neutron absorbing strength that is less than that of the neutron absorbing rod, is positioned within the inner housing, and is configured to receive the neutron absorbing rod therein.

A Control Neutron Absorber (CNA) assembly for a microreactor that produces nuclear energy is disclosed. The CNA assembly includes a housing, a CNA rod, and a burnable absorber. The housing includes an inner housing and an outer housing. The inner housing is configured to receive a CNA rod. The outer housing extends coaxially with the inner housing and is positioned radially outward and offset from the inner housing defining a cavity therebetween. The CNA rod includes a neutron absorbing rod including a first neutron absorbing material. The neutron absorbing rod is positioned within the inner housing and is configured to move axially relative to the inner housing. The burnable absorber includes a second neutron absorbing material, exhibits a neutron absorbing strength that is less than that of the neutron absorbing rod, is positioned within the inner housing, and is configured to receive the neutron absorbing rod therein.

A nuclear system. The nuclear system includes a fuel rod for use in a nuclear reactor. The fuel rod includes a cladding comprising an interior region, unspent fuel pellets housed in the interior region of the cladding, and a resonant electrical circuit supported within the interior region of the cladding. The resonant electrical circuit is configured to receive an excitation pulse through the cladding, and responsive to the received excitation pulse, generate a response pulse in the form of a magnetic field signal that is structured to travel wirelessly from the interior region and through the cladding. The nuclear system also includes a receiver positioned outside of the cladding and within the nuclear reactor. The receiver is configured to receive the response pulse and generate an output based on the received response pulse.

A nuclear system. The nuclear system includes a fuel rod for use in a nuclear reactor. The fuel rod includes a cladding comprising an interior region, unspent fuel pellets housed in the interior region of the cladding, and a resonant electrical circuit supported within the interior region of the cladding. The resonant electrical circuit is configured to receive an excitation pulse through the cladding, and responsive to the received excitation pulse, generate a response pulse in the form of a magnetic field signal that is structured to travel wirelessly from the interior region and through the cladding. The nuclear system also includes a receiver positioned outside of the cladding and within the nuclear reactor. The receiver is configured to receive the response pulse and generate an output based on the received response pulse.

An energy source using low-enriched nuclear fuel to produce heat contains a compact transportable pressure vessel containing a cylinder with the core with heating element formed by nuclear fuel and continually agitated by a directed flow of heat-exchange liquid, to which a second pressure vessel is connected with a closed water bath circuit and a heat exchanger for production of steam, while the compact transportable pressure vessel can be placed in a space selected from the group underground concrete space with stainless steel lining, sea-river vessel and container modification for road and/or railway transport.

An energy source using low-enriched nuclear fuel to produce heat contains a compact transportable pressure vessel containing a cylinder with the core with heating element formed by nuclear fuel and continually agitated by a directed flow of heat-exchange liquid, to which a second pressure vessel is connected with a closed water bath circuit and a heat exchanger for production of steam, while the compact transportable pressure vessel can be placed in a space selected from the group underground concrete space with stainless steel lining, sea-river vessel and container modification for road and/or railway transport.

A method of installing a temperature measuring device inside a reactor tube while filling the tube with catalyst is provided. The method includes inserting a positioning system, including a single inflatable bladder connected at a central location to a centering ring, into a reactor tube, the reactor tube comprising a distal end and a proximal end. Then inserting the centering ring around the temperature measurement device. Then locating the positioning system at a first predetermined distance from the distal end, and inflating the single inflatable bladder, thereby centering the centering ring and the temperature measurement device within the SMR tube. Then introducing catalyst into the SMR tube, thereby enclosing the temperature measurement device in catalyst.