| 摘要 |
<p>PURPOSE:To improve heat transfer performance not only in a dry condition but also in a wet condition by a method wherein the zigzag pattern of cut and raised surfaces is formed in such a manner that the cut and raised heights of slit pieces continuing in an air flow direction from fin surfaces are changed stepwise in the air flow direction. CONSTITUTION:Slit pieces 5 with cut and raised surfaces 6 in parallel to an air flow direction B are cut and raised in bridge-shape from fin 4 surfaces and installed at both sides of the fins 4. The cut and raised heights of the pieces 5 continuing in an air flow direction B are changed stepwise in five steps and the zigzag pattern of the surfaces 6 is formed continuously in the direction B. Thereby, in a dry condition, a high heat transfer rate between the fins 4 and the air flow B is obtained at a section covered from the upstream side to the downstream side, and also even in such a wet condition as water drops stick to the surface of the fins 4, a high heat transfer rate can be maintained between the fins 4 and the air flow B because of the formation of a zigzag flow passage. A heat exchanger with a fine heat transfer rate can in every point be obtained.</p> |
