Patent ID: 8505618

Claim:
A heat transfer fin for use in a fin-tube heat exchanger for exchanging heat between a first fluid and a second fluid, comprising: a plurality of heat transfer tube through-holes to which heat transfer tubes for passing the second fluid are to be fitted, the plurality of heat transfer tube through-holes being provided at regular intervals along a predetermined row direction intersecting a flow direction of the first fluid; a protuberance protruding from a surface of the fin, the protuberance being provided between two adjacent ones of the heat transfer tube through-holes; and a cut-out formed upstream of the protuberance in the flow direction of the first fluid, wherein: the protuberance has, as an upstream portion adjacent to the cut-out, a wing portion tapering toward an upstream side; each through-hole of the plurality of heat transfer tube through-holes is a through-hole that is formed at a position immediately adjacent to a leading edge portion of the heat transfer fin; and a portion or an entirety of the wing portion is located upstream of a line passing through respective centers of the plurality of heat transfer tube through-holes, with respect to the flow direction of the first fluid.