Abstract: A heat exchange tube for air conditioning and refrigeration applications is internally enhanced with helically arranged fins. The fins are separated from adjacent fins by a trough. The heat transfer coefficient is increased by forming the fins with a height-to-trough width ratio, h:T, of from 1.3:1 to 2.5:1. A further gain in heat transfer coefficient is achieved by fins having a normalized height (fin height/tube inside diameter) of at least 0.02.

Abstract: There is provided heat exchange tube formed from a ductile metal strip which is formed into a generally circular configuration with the opposing longitudinal edges of the strip welded together. Both surfaces of the strip are enhanced. One surface of the tube is enhanced with protrusions in the shape of truncated cones. The ratio of the pitch between longitudinally aligned protrusions and transversely aligned protrusions maximizes the formation and maintenance of vortexes in a flowing fluid along the tube surface.

Abstract: A thermoelectric refrigerator with a heat transfer system having a thermoelectric device and a heat exchanger with an evaporating surface and a condensing surface. A working fluid is sealed within the heat exchanger. The thermoelectric device includes a thermally conductive hot plate and a thermally conductive cold plate with thermoelectric elements disposed therebetween. The thermoelectric elements are preferably electrically coupled in series and thermally coupled in parallel. The evaporating surface of the heat exchanger is thermally coupled with the hot plate. A fluid flow path is provided to allow working fluid in its vapor phase to flow from the evaporating surface to the condensing surface and working fluid in its liquid phase to flow from the condensing surface to the evaporating surface. The configuration of the heat exchanger will optimize heat transfer by the working fluid from the thermoelectric device.

Abstract: A thermoelectric heat transfer system having a thermoelectric device and a heat exchanger with an evaporating surface and a condensing surface. A working fluid is sealed within the heat exchanger. The thermoelectric device includes a thermally conductive hot plate and a thermally conductive cold plate with thermoelectric elements disposed therebetween and the thermoelectric elements are electrically coupled in series and thermally coupled in parallel. The evaporating surface of the heat exchanger is thermally coupled with the hot plate. A fluid flow path to allow working fluid in its vapor phase to flow from the evaporating surface to the condensing surface and working fluid in its liquid phase to flow from the condensing surface to the evaporating surface.

Abstract: There is provided heat exchange tube formed from a ductile metal strip which is formed into a generally circular configuration with the opposing longitudinal edges of the strip welded together. Both surfaces of the strip are enhanced. On one surface, the enhancement constitutes parallel rows of vertical fins separated by channels. Conduits which run along the channels and are located at the base of one side of the fins facilitate bending of the fins about the fin base to form a nucleate boiling surface. On the opposing surface of the tube, the enhancement constitutes parallel rows of protrusions separated by a distance effective to generate turbulence in a fluid passing along the second surface. In a preferred embodiment, the protrusions are in the form of truncated cones.

Abstract: A method for the manufacture of an enhanced heat exchange tube, in which the internal surface area is increased by either minimizing the apex angle of internal fins or increasing the fin height. The fins are formed by annealing a metallic strip while inhibiting recrystallization grain growth, texturing metallic strip, deforming the textured metallic strip into a generally circular configuration and bonding opposing edges of the strip together to form a length of tube.

Abstract: Apparatus and method are disclosed for absorbing a subject vapor in an absorbent liquid wherein an additive is provided which exists in at least a vapor phase concurrently with the subject vapor, which additive is effective to reduce the surface tension of the absorbent liquid upon contact therewith. A heat transfer member is provided having a first surface over which absorbent liquid is passed such that a film is formed thereon, and a second surface over which a heat transfer fluid is passed in order to remove heat from the absorption process. Means are provided associated with the first surface of the heat transfer member for promoting interfacial turbulence between the film of absorbent liquid and the subject vapor such that a series of preferential absorption sites is established along the first surface.