Abstract: A metallic finned tube having multiple fins integrally formed on and extending helically on an outside of the tube. The fins number at least four and begin at fin run start locations spaced evenly about a circumference of the tube, with at least one group of side-by-side helical fins being formed which begin at substantially the same circumferential fin run start location on the tube exterior.

Abstract: A heat exchanger, in which a plurality of fins formed on either an internal or an external face of a heat transfer tube, wherein each of the plurality of fins has a first portion including a fin top and a second portion including a fin root, and wherein the first portion has a ridgeline formed in a raised and recessed shape, or in a wave-like or corrugated shape, and the second portion has a substantially straight outline in a fin longitudinal direction in a cross section parallel to either the internal or the external face on which the plurality of fins are formed.

Abstract: An evaporator of a refrigerator provided in a cool air passage includes a serpentine heat-exchanging pipe and a heat-exchanging member wound around the pipe. The heat-exchanging member is shaped in a band having two longitudinal edges. One longitudinal edge of the heat-exchanging member is contacted with the circumference of the pipe, and the other longitudinal free edge thereof has a plurality of cut-off portions. Respective axis of each straight portion of pipe are parallel to each other and in the direction of the air flow.

Abstract: The invention relates to a metallic heat-exchanger tube (1) with fins (2) which annularly or helically extend or rather extend in axial direction on the outside of the tube for condensing of vapor from pure substances or mixtures on the outside of the tube. To improve the condensation performance by effecting a thinning of a liquid film, the invention includes a making of the fins so that they have a constant fin height H throughout, with the fin flanks (4) being structured by spaced-apart depressions.

Abstract: The object of the present invention is to offer a heat transfer tube having a grooved inner surface, wherein the side edges of the board material do not form a waved shape and cracks do not form during tube expansion. In order to achieve this object, the grooved-inner-surface heat transfer tube of the present invention has a metallic tube with an inner circumferential surface, on which are formed a weld portion which extends in an axial direction of this metallic tube, a pair of projecting strip portions formed parallel to and separate from this weld portion, and a plurality of fins formed in an area between these projecting strip portions. The fins are formed with a constant angle with respect to the tube axis, and the ends of these fins are connected with the projecting strip portions. The thickness of the metallic tube within the grooves formed between the fins is made to increase in approaching the weld portion within an area surrounding the weld portion wherein the central angle is within 30.degree..

Abstract: Tube (1) internally grooved by helicoidal ribs (2) having a helix angle of 5.degree. to 50.degree., an apex angle (alpha) of 30.degree. to 60.degree.. The tube is characterized in that the ribs (2) form a periodic profile comprising at least two ribs of different heights, one designated high (2h) of a height Hh, and the other designated low (2b) of a height Hb, with a ratio Hb/Hh of 0.40 to 0.97, each high rib being bordered by a flat-bottomed groove (3).

Abstract: An improved radiant heat transfer tube with internal fins is provided. Optimum design characteristics for the number of fins, the height or length of the fins and the twist of the fins is provided to enhance convective and radiant heat transfer from combustion gases inside the tube to the inside surface of the tube. The fin design applies to tubes fabricated from high temperature metal alloys, monolithic ceramics, metal matrix composites or ceramic matrix composites.