FINNED TUBE HEAT EXCHANGER WITH SECONDARY STAR FINS AND METHOD FOR ITS PRODUCTION

摘要

The heat exchange efficiency of a finned tube heat exchanger is increased by providing secondary heat exchange surfaces which are dimensioned and configured to maximize heat exchange with the surrounding fluid. These secondary heat exchange surfaces, formed from materials which would normally be wasted when blanks are removed from the fins to form apertures for receiving the tubes, are formed by bending the preserved materials into star-shaped structures which increase the surface area in contact with the surrounding fluid. The secondary heat exchange surfaces increase the surface area of the fin which is available for heat exchange, and provide this increased surface area at a location maximizing heat transfer capability to the surrounding fluid and to the tubes. The heat exchanger can be constructed in a simple and inexpensive process while preventing fin presses or related machinery from being jammed by removed materials.