摘要 |
A tube for heat transfer in which the inner surface of the tube is grooved into a pattern. The pattern includes a first fin (10) and a second fin (20) which have different shapes, wherein the first fin comprises a shaft and a head integrally formed, the shaft extending from the inner surface in a direction away from the inner surface, the head extending from the shaft in a direction away from the inner surface. In a transverse cross section of the tube, the circumferential width of the head is larger than that of the shaft. |