Arrangement for supporting U-bend tube sections in the high heat environment of steam generators using flat bars. The invention uses a combination of thicker and thinner flat bars to impart a serpentine path to the arc of the normally curvilinear U-tubes. The support system accommodates the dilation and contraction of coolant tubes and other elements caused by the extreme and varying conditions inside a steam generator, and which can cause gaps between coolant tubes and prior art tube support bars. Bars of alternating thickness provide alternating offsets to tensionally push and support each tube on multiple sides and in multiple locations, and this tension keeps the tubes in contact with at least some flat bars on multiple sides regardless of size and shape changes. Support arrangement includes a set of fan bars, each fan bar including thick and thin flat bars projecting up and out from a collector bar.

A heat exchanger includes a body having an inlet header through which a fluid is introduced, and an outlet header through which the fluid is discharged; and one or more plates accommodated in the body and provided with flow path modules providing flow paths for the fluid introduced through the inlet header to flow to the outlet header. The heat exchanger further includes at least one flow path adjuster each having at least a portion thereof accommodated in the body and being movable or rotatable to open or close a part or all of the flow paths or to change directions of the flow paths so that a flow of the fluid is adjusted.

A heat dissipation structure includes a housing. The housing has a bottom surface, a liquid inlet channel, a liquid outlet channel and a protruding portion. The liquid inlet channel and the liquid outlet channel are located at two opposite ends of the housing and above the bottom surface. The liquid inlet channel and the liquid outlet channel extend along a first direction. The protruding portion is located between the liquid inlet channel and the liquid outlet channel and above the bottom surface. The protruding portion protrudes towards a direction away from the bottom surface. The protruding portion has a protruding surface facing away from the bottom surface. A distance between the protruding surface and the bottom surface is increased first and then decreased along the first direction.

A heat exchanger module having at least two fluid circuits, of longitudinal axis including a stack of plates, defining at least two fluid circuits, at least a part of the plates each including fluid circulation channels, the channels of at least one of the two circuits, referred to as first circuit, having at least one fluid supply and distribution zone for supplying and distributing fluid from outside the stack, forming a fluid pre-header, in which zone the channels are delimited by studs distributed over the surface of the plate; an exchange zone continuous with the pre-header and wherein the channels are each delimited by a groove separated from one another by a rib and extending along the longitudinal axis.

A thermochemical method for storing and releasing thermal energy by means of a compound in solid form of formula AO.sub.xB.sub.y.zH.sub.2O, in which: A is an element selected from uranium (U) and thorium (Th); O is the element oxygen; B is an anion or an oxoanion; x is a number comprised between 0 and 4; y is a number comprised between 0 and 2; z is a number greater than 0 and less than 10; it being understood that at least one of x and y is different from 0 and that the compound of formula Th(SO.sub.4).sub.2.xH.sub.2O is excluded.

The present invention relates to a passive pulse water flow adjustment device for water flow cooling. The device includes a water storage container and a pulse water flow adjustment structure, wherein the water storage container is arranged in front of a to-be-cooled high-temperature wall surface through the pulse water flow adjustment structure, and the pulse water flow adjustment structure provides a non-continuous pouring pulse water flow for the high-temperature wall surface. This device is used to cool the high-temperature wall surface, and when being cooled, the high-temperature wall surface is poured by the pulse water flow.

A system for transferring heat from a nuclear reactor comprises a nuclear reactor comprising a nuclear fuel and a reactor vessel surrounding the nuclear reactor and a heat transfer system surrounding the nuclear reactor. The heat transfer system comprises an inner wall surrounding the nuclear reactor vessel, first fins coupled to an outer surface of inner wall, an outer wall between the inner wall and a surrounding environment, and second fins coupled to an inner surface of the outer wall and extending in a volume between the outer surface of the inner wall and the inner surface of the outer wall, the outer surface of the inner wall and the first fins configured to transfer heat from the nuclear reactor core to the second fins and the inner surface of the outer wall by thermal radiation. The heat transfer system may be directly coupled to the nuclear reactor vessel, or may be coupled to an external reflector surrounding the nuclear reactor vessel. Related heat transfer systems and systems for selectively removing heat from a nuclear reactor are disclosed.

The invention relates to the nuclear energy field, including systems for passive heat removal from the pressurized water reactor through the steam generator. The invention increases heat removal efficiency, coolant flow stability and system reliability. The system includes at least one coolant circulation circuit comprising a steam generator and a section heat exchanger above the steam generator in the cooling water supply tank and connected to the steam generator through the inlet and outlet pipelines. The heat exchanger is divided into parallel sections wherein L/D≦20, L being the half-section length, D being the header bore, and includes an upper and lower header interconnected by heat-exchange tubes, startup valves with different nominal bores are installed on the outlet pipeline. The inlet and outlet pipeline sections of the circulation circuit comprise a set of branched parallel pipelines individually connected to each of the above heat exchanger sections.

Illustrative embodiments provide nuclear fission fuel elements, and systems, applications, apparatuses, and methods related thereto. Illustrative embodiments and aspects include, without limitation, nuclear fission fuel elements, heat pipe assemblies, heat pipes, methods of fabricating a nuclear fission fuel element, methods of fabricating a heat pipe assembly, and the like.

A modular plate and shell heat exchanger in which welded pairs of heat transfer plates are tandemly spaced and coupled in parallel between an inlet and outlet conduit to form a heat transfer assembly. The heat transfer assembly is placed in the shell in order to transfer heat from a secondary to a primary fluid. Modules of one or more of the heat transfer plates are removably connected using gaskets at the inlet and outlet conduits which are connected to a primary fluid inlet and a primary fluid outlet nozzle. The heat transfer assembly is supported by a structure which rests on an internal track which is attached to the shell and facilitates removal of the heat transfer plates. The modular plate and shell heat exchanger has a removable head integral to the shell for removal of the heat transfer assembly for inspection, maintenance and replacement.