Heat exchanger

A heat exchanger module comprising:

• a hollow chamber including an inner volume forming a flow passage for a first fluid and having a first surface;
• hollow enclosures each extending outwardly from the first surface and having a root extending through the first surface into the inner volume, wherein each of the hollow enclosures contains a working fluid which undergoes a phase change in the hollow enclosures during an operative mode of the heat exchanger module, and the working fluid is in thermal communication with the first fluid through the root of each of the hollow enclosures, and
• channels defined by gaps between the hollow enclosures, wherein the channels form flow passages for a second fluid in thermal communication with the working fluid,
• wherein the flow passage extends from a first fluid inlet on an first side of the hollow chamber to a first fluid outlet on a second side of the hollow chamber opposite to the first side.

A heat exchanger module for an aircraft, the heat exchanger module comprising:

• a hollow chamber including an inner volume forming a flow passage for a first fluid and having a first surface;
• hollow enclosures each extending outwardly from the first surface and having a root extending through the first surface into the inner volume, wherein each of the hollow enclosures contains a working fluid which undergoes a phase change in the hollow enclosures during an operative mode of the heat exchanger module, and the working fluid is in thermal communication with the first fluid through the root of each of the hollow enclosures, and
• channels defined by gaps between the hollow enclosures, wherein the channels form flow passages for a second fluid in thermal communication with the working fluid,
• wherein at least one of the hollow enclosures is configured to be coupled to an outer skin of the aircraft.