| 摘要 |
Tubing having internal fins projecting inward from the tube wall, each fin having an external surface that includes multiple acute interior angles or crevices that may form nucleation boiling sites, heat exchangers comprising such tubing, and methods of making same. Acute angles, crevices, or elongated slits may be formed in the sides, center, or both, of the fins or between the fins and the tube wall, and convex rounded surfaces may be provided therebetween. Fins may be parallel to the tube centerline or helically wound. Tubing may be expanded with a bullet which may form an interference fit with external fins, may modify the fins to create more effective nucleate boiling cavities, or both.
|
