Patent Number: 
Section: claims

1. A heat exchanger module with longitudinal axis (X) comprising a stack of plates defining at least two fluid circuits, at least some the plates each comprising fluid circulation channels each delimited at least in part by a groove, the channels of at least one of the two circuits, termed the first circuit, including:a zone (Z1), termed the feeding zone, of feeding the fluid from the exterior of the stack, in which the channels are parallel to one another and extend along a secant axis (X′) intersecting the longitudinal axis (X) and in which two adjacent channels communicate with one another via at least one notch formed in a rib separating their respective grooves;a zone (Z3) termed the bifurcation zone in which each channel is divided into at least two straight channels parallel to one another and parallel to the longitudinal axis (X), being separated from one another by a rib;a zone (Z2) termed the connection zone between the feeding zone and the bifurcation zone, in which each channel has a straight profile that extends along the secant axis (X′) and a curved profile continuous with the straight profile in order to connect the channel with a straight channel of the bifurcation zone;a zone (Z4) of continuous exchange with the bifurcation zone in which the parallel straight channels separated from one another by ribs extend parallel to the longitudinal axis (X);wherein the channels of each plate of the first circuit communicate with those of the other plates of the first circuit in their respective feed zone (Z1), via openings, made in each channel of the feeding zone, passing through the stack but not communicating with the channels of the second circuit,the notches and the openings forming a jet-break grille for rebalancing the flows of the fluid between the channels of the first circuit when said fluid is circulating in said channels. 2. The heat exchanger module as claimed in claim 1, wherein the curved profile of each channel of the first circuit comprises two curves to connect the straight profile of the connection zone to the straight channel of the bifurcation zone. 3. The heat exchanger module as claimed in claim 1, wherein each straight channel is divided into four channels in the bifurcation zone (Z3). 4. The heat exchanger module as claimed in claim 1, wherein the angle between the secant axis (X′) and the longitudinal axis (X) of the module is between 0 and 45° inclusive. 5. The exchanger module as claimed in claim 1, wherein a plate of the first circuit is inserted between two plates of the other of the two circuits, termed the second circuit, at least in the central part of the stack. 6. The exchanger module as claimed in claim 1, wherein the channels of the first circuit have an oval, circular, rectangular or square section. 7. A method of producing a heat exchanger module as claimed in claim 1, comprising the following steps:machining grooves in first metal plates in order to constitute the channels of the first circuit configured with the feed, connection, bifurcation and exchange zones;machining grooves in second metal plates in order to constitute the channels of other of the two circuits, termed the second circuit;stacking in an alternating manner the first plates and the second plates so as to have the through-openings that enable communication between channels of the plates of the first circuit but not with those of the plates of the second circuit;assembling the first and second metal plates to one another, either by hot isostatic compression (HIC), or by a process termed a hot uniaxial diffusion welding process, so as to obtain welding by diffusion between them, or by brazing. 8. The use of a heat exchanger comprising a plurality of heat exchanger modules as claimed in claim 1, wherein the fluid of the first circuit, by way of primary fluid is a liquid metal and the fluid of a second circuit, by way of a secondary fluid, being a gas or a gas mixture. 9. The use as claimed in claim 8, wherein the fluid of the second circuit comprises mainly nitrogen and the fluid of the first circuit being liquid sodium. 10. The use as claimed in claim 8, wherein the fluid of the first or second circuit comes from a nuclear reactor. 11. A nuclear installation comprising a fast neutral nuclear reactor cooled with liquid metal, notably a liquid sodium cooled fast reactor (SFR) and a heat exchanger comprising a plurality of exchanger modules as claimed in claim 1.