A heat dissipating device which is liquid cooled includes a base and at least one heat dissipation fin connected to the base. The base includes a first cavity. The at least one heat dissipation fin comprising a second cavity communicating with the first cavity, the second cavity and the first cavity together form an accommodation cavity for accommodating a working fluid which forcefully applies cooling upon being heated sufficiently to be vaporized.

A heat exchanger (4) has fluid flow channels (6) with at least one heat exchanging surface (10) which has an undulating surface section for which the surface profile varies along a predetermined direction such that at a first edge (E1) the surface profile follows a first transverse wave (20), at a second edge (E)2 the surface profile follows a second transverse wave (22) and at an intermediate point I between the edges the surface profile follows a third transverse wave (24). The third transverse wave (24) has a different phase, frequency or amplitude to the first and second transverse waves so that chevron-shaped ridges and valleys are formed. This improves the mixing of fluid passing through the channel and hence the heat exchange efficiency.

The invention relates to a heat transfer tube (9) for falling film evaporation having a heating medium surface (21) to be heated by a heating medium, a falling film surface (20) to have spent liquor passing over it, and being made from an sheet metal material. The falling film surface of the heat transfer tube is equipped with a multitude of wire bumps (WB), each wire bump being spaced apart along the longitudinal axis (CC) of the heat transfer tube from a neighbouring wire bump by 3-300 mm, said wire bumps (WB) having a height (h) in the range 0.3 to 5.0 mm, a width (w) in the range 0.3-5.0 mm, and an inclination angle (a) versus a plane orthogonal to a longitudinal axis (CC) of the heat transfer tube in a range of 0-70 degrees. The invention also relates to a method for manufacturing said heat transfer tube.

The invention relates to a heat transfer tube (9) for falling film evaporation having a heating medium surface (21) to be heated by a heating medium, a falling film surface (20) to have spent liquor passing over it, and being made from an iron based high alloy stainless steel material with an alloy content above 16.00% for Chromium and above 1% for Nickel. The falling film surface of the heat transfer tube is equipped with at least one weld ridge (WR; WR.sub.1, WR.sub.2), said weld ridge having a height (h; h.sub.2) in the range 0.3 to 5.0 mm, a width (w; w.sub.2) in the range 0.5-15 mm, and an inclination angle (; .sub.1, .sub.2) versus a plane orthogonal to a longitudinal axis (CC) of the heat transfer tube in a range of 0-70 degrees so that each weld ridge is inclined and extends helically along at least a portion of the heat transfer tube or extend within a plane orthogonal to the longitudinal axis of the heat transfer tube and forms well ridge portions on the falling film surface such that the distance along the longitudinal axis of the heat transfer tube between adjacent weld ridge portions is within the range of 0 to 250 mm. The invention also relates to a method for manufacturing said heat transfer tube.

The present disclosure provides a heat exchanger flat tube and a heat exchanger with the heat exchanger flat tube, the heat exchanger flat tube includes two plates opposite to each other, a fluid passage is formed between the two plates, a turbulence structure is provided in the fluid passage and has a gradually expanding portion and a gradually narrowing portion, both an extension direction of the gradually expanding portion and an extension direction of the gradually narrowing portion are consistent with a flow direction of a fluid, and the gradually narrowing, portion is located downstream of the gradually expanding portion along the flow direction of the fluid.

The double tube for heat exchange includes: a spiral pipe having ridges and valleys alternately formed on a circumferential surface along a spiral track thereof and guiding a first fluid therethrough; an outer pipe receiving the spiral pipe axially inserted thereinto and guiding a second fluid along the circumferential surface such that the second fluid exchanges heat with the first fluid; a resistance member protruding from the spiral pipe or valleys to increase time of the second fluid in the valleys and to support the ridges adjacent thereto. Unlike typical double tubes, this double tube can: improve heat exchange efficiency by virtue of the spiral pipe; improve flow directionality of the second fluid; reduce noise through expansion of a space between an end joint of the outer and inner pipe to reduce the pressure of the second fluid; and improve efficiency through resistance members protruding from the valleys.

A tube for a thermal transfer device can include a wall having a length and having an inner surface and an outer surface, wherein the inner surface forms a cavity. The tube can also include at least one first dimple pressed into the wall toward the cavity at a first location along the length of the wall, where the inner surface of the wall at the at least one first dimple is separated from itself by a first distance. The tube can further include at least one second dimple pressed into the wall toward the cavity at a second location along the length of the wall, where the inner surface of the wall at the at least one second dimple is separated from itself by a second distance. The cavity can be configured to receive a fluid that flows continuously along a length of the at least one wall.

A heat exchanger is configured to perform heat exchange by boiling a liquid by heat transfer from a heat source to the liquid through a heat transfer member. In the heat exchanger, a first heat conduction region and a second heat conduction region are alternately provided in a form of stripes on a surface on a side that contacts the liquid such that the liquid boils via a heat transfer member.

A device for forming inside three-dimensional finned tube by multi-edge ploughing and extruding, comprises a machine frame, a machine head, a supporting mechanism, an axial feeding mechanism and a cutter assembly for forming inside fins. The machine head, the supporting mechanism and the axial feeding mechanism are axially mounted on the machine frame in sequence. The cutter assembly for forming inside fins is mounted on the feeding mechanism. One end of a metal tube to be machined for forming inside three-dimensional fins is clamped on a chunk of a rotary main shaft of the machine head, and the other end thereof is placed on the supporting mechanism. The rotary main shaft of the machine head provides the rotation power for the metal tube, and the axial feeding mechanism drives the cutter assembly to move linearly along a coaxial line of the metal tube and the cutter assembly.

A heat exchanger may include an outer casing extending in a longitudinal direction and delimiting a volume through which a first fluid is flowable, and a tube bundle including a plurality of tube bodies arranged in the volume and through which a second fluid is flowable. In a cross section, the volume may have an inner surface area and an inner circumference and each tube body may have an outer circumference and an outer surface area. A ratio of a sum of the outer circumferences to the inner circumference may be at least 5.5, and a sum of the outer surface areas may account for 64% or less of the inner surface area. A residual cross section area of the inner surface area may be delimited between the outer casing and the plurality of tube bodies.