| 摘要 |
PURPOSE: A heat transfer tube is provided to achieve an improved refrigerating efficiency with a reduced power consumption. CONSTITUTION: A heat transfer tube(10) has a cavity(12) with a mesh-shaped cavity entrance(12a). The cavity is formed by processing, using a disk knife, the surface of the heat transfer tube in the axial direction and centrifugal direction of the heat transfer tube. Thus, a heat transfer fin(14) shaped as a segment having square cross section is formed. The cavity is connected to one another in accordance with the square cross section of the heat transfer fin. The heat transfer tube has a twisted ridge(16) formed at the inner diameter of the heat transfer tube. The cavity is formed to have a wider upper portion and a narrower lower portion, forming an elliptical surface from the cavity entrance down to a bottom surface(12b) of the cavity. The size of the cavity entrance ranges from 0.13mm to 0.15mm, and the depth of the cavity ranges 0.8mm +/- 0.03mm.
|
