DOUBLE TUBE FOR HEAT EXCHANGER

摘要

A double tube for a heat exchanger, capable of being used without generating noise during operation and allowing the heat exchanger to exhibit excellent heat exchange performance. A double tube (1) for a heat exchanger has a double tube configuration having an inner tube (2) disposed within the outer tube (10) and is used for heat exchange between fluid which flows inside the inner tube (2) and fluid which flows between the inner tube (2) and the outer tube (10). The cross-sectional shape of the inner tube (2) is a triangle having the apexes (21) formed as circular arc curved surfaces, and the positions of the apexes (21) are helically displaced in the longitudinal direction. The cross-sectional shape of the outer tube (10) is that of a smooth circular tube. The inner peripheral surface of the outer tube (10) and the apexes (21) of the inner tube (2) are in contact with each other, and three outer flow paths (31) which are divided in the circumferential direction are formed between the outer tube (10) and the inner tube (2). The inner tube (2) and the outer tube (10) preferably consist of an aluminum alloy or a copper alloy.