Abstract: A plate fin heat exchanger is disclosed. The heat exchanger includes a plurality of plates defining a set of hot fluid passages between adjacent plates of the plurality of plates and a set of cold fluid passages between adjacent plates of the plurality of plates. A hot fluid inlet and outlet are located at a first face of the heat exchanger. A barrier is located between adjacent plates defining the hot fluid passages. The barrier extends between the adjacent plates and extends from the first face of the heat exchanger at a location between the hot fluid inlet and the hot fluid outlet in a direction perpendicular to the first face, and defines a first pass of hot fluid passages on a first side of the barrier and a second pass of hot fluid passages on a second side of the barrier.

Abstract: A heat exchanger includes a heat exchanger wall that bounds a passage. A coating lines the heat exchanger wall. The coating has a thickness that varies according to location on the heat exchanger wall.

Abstract: A method of extending the lifetime of brazed primary hot inlet wavy fin structures of aircraft heat exchangers includes inserting slots in the fins. The slots increase the mechanical compliance of the fins as well as act as crack arrestors should a thermally induced fracture occur. In an embodiment, the slots are inserted by EDM.

Abstract: A plate fin heat exchanger is disclosed. The heat exchanger includes a plurality of plates defining a set of hot fluid passages between adjacent plates of the plurality of plates and a set of cold fluid passages between adjacent plates of the plurality of plates. A hot fluid inlet and outlet are located at a first face of the heat exchanger. A barrier is located between adjacent plates defining the hot fluid passages. The barrier extends between the adjacent plates and extends from the first face of the heat exchanger at a location between the hot fluid inlet and the hot fluid outlet in a direction perpendicular to the first face, and defines a first pass of hot fluid passages on a first side of the barrier and a second pass of hot fluid passages on a second side of the barrier.

Abstract: A plate fin heat exchanger includes a plurality of finned cold layers configured to conduct a first fluid, and a plurality of finned warm layers configured to conduct a second fluid. The finned warm layers include an inlet side and an outlet side. A first portion of fins of at least one finned warm layer of the plurality of finned warm layers includes a plurality of aligned peaks and valleys defining a wave configuration for each fin of the first portion of fins. An upstream leading edge of the first portion of fins begins at a point of the wave configuration that is at least one of the peaks and valleys.

Abstract: In one aspect, a plate fin heat exchanger is provided. The heat exchanger includes a plurality of finned cold layers configured to conduct a first fluid and a plurality of finned warm layers configured to conduct a second fluid. The finned warm layers include an inlet side, an outlet side, a first portion of fins at the inlet side, and a second portion of fins at the outlet side.

Abstract: A heat exchanger includes a plurality of mini-channel tubes. The mini-channel tubes extends for an axial length defined between two manifolds. The mini-channel tubes include a plurality of generally rectangular flow passages. The generally rectangular flow passages are aligned adjacent to each other to define a lateral dimension. A first lateral width of the generally rectangular passages is defined with a ratio of the axial length to the first lateral width being between 201.3 and 215.3. An aircraft system is also disclosed.

Abstract: A method of extending the lifetime of brazed primary hot inlet wavy fin structures of aircraft heat exchangers includes inserting slots in the fins. The slots increase the mechanical compliance of the fins as well as act as crack arrestors should a thermally induced fracture occur. In an embodiment, the slots are inserted by EDM.

Abstract: A core assembly for a heat exchanger includes a plurality of parting sheets defining a plurality of fluid passages including a plurality of first fluid passages and a plurality of second fluid passages arranged in an alternating arrangement, wherein each of the plurality of parting sheets comprises a thickness of about 0.016?. Also included is a plurality of first fluid passage fins disposed between the plurality of parting sheets within each of the plurality of first fluid passages. Further included is a plurality of second fluid passage fins disposed between the plurality of parting sheets within each of the plurality of second fluid passages. Yet further included is a plurality of closure bars disposed between respective pairs of the plurality of parting sheets.

Abstract: A channel tube includes a body having first and second surfaces extending between first and second opposing ends to define a tube width. The first and second surfaces are separated from each other by a distance defining a tube height. A plurality of ports extend through the body and between the first and second surfaces to define a fluid path extending in a direction of the tube width. Each port defines a plurality of walls and a plurality of ribs having a thermal conductive surface to transfer heat therethrough. A first wall extends in a direction of the tube width. The second wall extends in a direction of the tube width and is disposed opposite the first wall. At least one rib is integrally formed between the first and second walls and extends perpendicular thereto.

Abstract: A heat exchanger includes a plurality of mini-channel tubes. The mini-channel tubes extends for an axial length defined between two manifolds. The mini-channel tubes include a plurality of generally rectangular flow passages. The generally rectangular flow passages are aligned adjacent to each other to define a lateral dimension. A first lateral width of the generally rectangular passages is defined with a ratio of the axial length to the first lateral width being between 201.3 and 215.3. An aircraft system is also disclosed.

Abstract: A heat exchanger includes a heat exchanger wall that bounds a passage. A coating lines the heat exchanger wall. The coating has a thickness that varies according to location on the heat exchanger wall.