Heat transfer augmentation in a circular tube using V-wavy twisted tape

Abstract

This research studied heat transfer performance in circular tubes installed with V-wavy twisted tape (V-WTT). The V-wavy twisted tape was made of a thin straight aluminum sheet 1.0 millimeter thick, a width of 37.5 millimeter, constant twist ratio (y/W) of 3.0 and V-wavy angles (q) of 30° and 60°, Respectively. The test tube was a copper having an internal diameter of 38 millimeter and a length of 1,600 millimeter. Air was used as a working fluid for Reynolds numbers (Re) ranging from 4,000 to 8,000 under uniform wall heat-flux condition. The heat transfer, friction loss and thermal performance behaviors were determined. The experimental results showed that the test tube with the V-wavy twisted tape having (q) of 30° at Re of 4,000 gave the maximum heat transfer performance of 1.24.