PURPOSE: To enhance the external heat transfer and improve the ease of handling by extending the ridge of an external fin like a hook to one of the sides of a groove, and extending the hook to the valley of an adjacent external fin.
CONSTITUTION: An external fin 12 has a ridges 16 and valleys 18 alternately in the direction of its length, and the external fin 12 is divided by the valleys 18. The valleys 18 are arranged parallelly to each other but at an angle of 10-60° relative to the normal line to the fin length. The respective ridges 16 are extended more toward their peak like a hook to at least one groove 14b of the grooves 14a, 14b present on either side. The hook configuration 20 extends toward the groove 14b and becomes sharper as it approaches the slope 16a of one of the valley 18 between the slopes 16a, 16b on either side of the fin length. Therefore, more contact area becomes available for the condensible gas, improving the condensing efficiency. Moreover, when the heat transmission pipes are superposed, the mutual intrusion between the ridges can be prevented.
TAKEDA IWAO
HASHIMOTO HIROMI
HIRAMATSU YOSHIHIRO
| JPS559639A | 1980-01-23 | |||
| JPS5238666A | 1977-03-25 |