A double pipe type heat exchanger includes an inner pipe having a first flow path defined therein and an outer pipe arranged around the inner pipe to define a second flow path between the inner pipe and the outer pipe. The inner pipe includes a spiral groove formed on an outer circumferential surface of the inner pipe to extend along a longitudinal direction of the inner pipe. The outer pipe includes a reduced diameter portion protruding inwardly so that the inner surface of the outer pipe is intermittently contacted with the outer circumferential surface of the inner pipe.

A heat exchanger includes fins each housed in a respective one of tubes. Each of the fins includes a connecting portion that corrugated for a predetermined fin pitch and that has peaks joined to an inner surface of a wall of each of the tubes and a non-connecting portion that is not joined to the inner surface of the wall of the each of the tubes. The non-connecting portion has a length longer than the predetermined fin pitch. The wall of the each of the tubes has a protrusion to face the non-connecting portion.

A method for transfer of heat between a first and a second fluid, wherein the first and the second fluid circulate respectively on both sides of a thermally conductive wall of a monobloc assembly formed in a single piece. The monobloc assembly, which is arranged in the interior of a device, includes: a first, three-dimensional, cellular, thermally conductive structure through which the first fluid can pass; at least the thermally conductive wall; and a second, three-dimensional, cellular, thermally conductive structure through which the second fluid can pass. The first and second three-dimensional, cellular structures are situated on both sides of and integral with the wall such that heat transfer is carried out from the first to the second fluid through the wall, and both first and second fluids are under liquid phases and under gaseous phases, with the liquid phases circulating in a direction opposite that of the gaseous phases.

A finned tube (e.g., for use in a flooded and falling film evaporator) is provided. The finned tube includes a tube body with an interior surface and an exterior surface. The finned tube may include a plurality of adjacent helical fins (e.g., continuously or intermittently) protruding circumferentially around the exterior surface of the tube body. At least one channel is disposed between the plurality of adjacent helical fins. Each respective helical fin includes at least one sidewall and a fin top. Each channel includes at least one channel enhancement impressed radially into and transversely through at intervals around the circumference of the exterior surface of the tube body. The finned tube may also include at least one top enhancement and/or sidewall enhancement impressed radially into and transversely through at intervals around the circumference of the exterior surface of the tube body.

A heat exchanger includes first and second fluid circuits. The first fluid circuit is formed by a first set of fins, a first inlet header, and a first outlet header. The first set of fins extend radially and are coaxial with each other. The first inlet header is fluidly connected to and is disposed on an upstream end of the first fins. The first outlet header is fluidly connected to and is disposed on a downstream end of the first fins. The second fluid circuit is formed by a second set of fins, a second inlet header, and a second outlet header. The second fins extend radially and are coaxial with each other. An annular shape of the second inlet header conforms to the circular shape of the first inlet header. An annular shape of the second outlet header conforms to the circular shape of the first outlet header.

A heat exchanger according to an embodiment of the present disclosure and an air conditioner having the same include a heat transfer tube through which a refrigerant passes, a fin having a mounting hole in which the heat transfer tube is installed, and a fin collar extending from the mounting hole and being in contact with the heat transfer tube by the expansion of the heat transfer tube, wherein the fin collar includes a base portion provided adjacent to the fin and extending to be bent at a first curvature radius, and a distal end located on the opposite side of the base portion and extending to be bent at a second curvature radius smaller than the first curvature radius.

A heat exchanger tank that includes external ribs that provide reinforcement to structure of the heat exchanger tank is disclosed. In addition, at least one reinforcement element may engage with an external tank portion and may be tensioned by press fitting the at least one reinforcement element on the external tank portion such that limbs of the at least one reinforcement element are separated by the external tank portion between the external ribs. The at least one reinforcement element may further be maintained in the tensioned configuration by using at least one retention means.

An additively-manufactured heat exchanger includes fluidly-separated alternating first and second layers having respective flow channels which can include one or more features that is either a riblet or a turbulator. A riblet includes a riblet peak and/or a riblet valley, which has a riblet slope, and the riblet peak and/or riblet valley has a riblet axis that is generally parallel to either the first fluid flow direction or the second fluid flow direction. A turbulator includes a turbulator peak and/or a turbulator valley, which has a turbulator slope, and the turbulator peak and/or turbulator valley has a turbulator axis that is generally perpendicular to either the first fluid flow direction or the second fluid flow direction. The respective slope angles are generally 25-65 deg. relative to build-axis, thereby resulting in improved surface roughness and uniformity control during the build process.

A compact gas-gas heat exchange tube. The heat exchange tube includes a heat transfer tube which is configured to separate an in-tube fluid from an out-tube fluid, and achieve, through convection and heat conduction manners, heat transfer between the in-tube fluid and the out-tube fluid; an inner fin set which is configured to expand a heat exchange surface on an inner side of the heat transfer tube, form a micro-channel to separate the in-tube fluid to make the same to axially flow along the heat transfer tube, and produce a turbulence effect and enhance heat convection as well; an outer fin set which is configured to expand a heat exchange surface on an outer side of the heat transfer tube, form a micro-channel to restrict the out-tube fluid from axially and reversely flowing along the heat transfer tube, and produce a turbulence effect and enhance heat convection as well, wherein a hole is provided on each fin of the inner fin set or/and the outer fin set. The present invention further provides methods for manufacturing and using the compact gas-gas heat exchange tube. The present invention realizes complete reverse flow and efficient heat transfer in a limited space and under a heat exchange working condition of a small logarithmich mean temperature difference, saves a spatial dimension of the apparatus, and reduces a weight of each area as well so as to reduce a total weight and a manufacturing cost.

A heat exchanger includes first and second fluid circuits. The first fluid circuit is formed by a first set of fins, a first inlet header, and a first outlet header. The first set of fins extend radially and are coaxial with each other. The first inlet header is fluidly connected to and is disposed on an upstream end of the first fins. The first outlet header is fluidly connected to and is disposed on a downstream end of the first fins. The second fluid circuit is formed by a second set of fins, a second inlet header, and a second outlet header. The second fins extend radially and are coaxial with each other. An annular shape of the second inlet header conforms to the circular shape of the first inlet header. An annular shape of the second outlet header conforms to the circular shape of the first outlet header.