Heat exchanger including furcating unit cells

A heat exchanger comprising:

• a core defining a first passageway for a first fluid to flow through and a second passageway for a second fluid to flow through, the core comprising an assembly comprised of:
• a first unit cell of the unit cells that are coupled together in the assembly having sidewalls that define first passageways into, through, and out of the first unit cell with the first passageways having square cross-sectional shapes, the sidewalls of the first unit cell in the unit cells that are coupled together in the assembly forming at least one inlet through which a first fluid flows into the first unit cell of the unit cells that are coupled together in the assembly, the sidewalls of the first unit cell in the unit cells that are coupled together in the assembly shaped to furcate flow of the first fluid inside the first unit cell in the unit cells that are coupled together in the assembly into plural different outlets of the first unit cell that also are formed by the sidewalls;
• a second unit cell of the unit cells coupled together in the assembly coupled to the first unit cell of the unit cells coupled together in the assembly;
• and
• a third unit cell of the unit cells coupled together in the assembly coupled to the first unit cell of the unit cells coupled together in the assembly,
• wherein the sidewalls of the unit cells that are coupled together in the assembly engage the sidewalls of one or more other unit cells of the unit cells that are coupled together in the assembly to form second passageways in which a second fluid flows, the second passageways located outside of and between the unit cells that are coupled together in the assembly, the first passageways located inside of the unit cells that are coupled together in the assembly, the first passageways and the second passageways separated from each other only by the sidewalls of the unit cells that are coupled together in the assembly,
• wherein each of the at least one inlet and the outlets of each of the unit cells that are coupled together in the assembly have a first hydraulic diameter that is one half of a second hydraulic diameter of the second passageways.

A heat exchanger comprising:

• a core defining a first passageway configured for a first fluid to flow through and a second passageway configured for a second fluid to flow through, the core comprising:
• an assembly comprised of unit cells coupled together, a unit cell of the unit cells that are coupled together in the assembly having sidewalls that define first passageways into, through, and out of the unit cell with the first passageways having square cross-sectional shapes, the sidewalls of the unit cell in the unit cells that are coupled together in the assembly forming at least one inlet through which a first fluid flows into the unit cell of the unit cells that are coupled together in the assembly, the sidewalls of the unit cell in the unit cells that are coupled together in the assembly shaped to furcate flow of the first fluid inside the unit cell in the unit cells that are coupled together in the assembly into plural different outlets of the unit cell that also are formed by the sidewall,
• wherein the sidewalls of the unit cell of the unit cells that are coupled together in the assembly engage the sidewalls of one or more other unit cells of the unit cells that are coupled together in the assembly to form second passageways in which a second fluid flows, the second passageways located outside of and between the unit cells that are coupled together in the assembly, the first passageways located inside of the unit cells that are coupled together in the assembly, the first passageways and the second passageways separated from each other only by the sidewalls of the unit cells that are coupled together in the assembly,
• wherein each of the at least one inlet and the outlets of each of the unit cells that are coupled together in the assembly have a first hydraulic diameter that is one half of a second hydraulic diameter of the second passageways,
• wherein the core further comprises a first header and a second header, the first header configured for the first fluid to flow from the first header into the first passageway in a first direction, the second header configured for the second fluid to flow from the second header into the second passageway in a second direction transverse to the first direction.