Patent ID: 9714794
Date: 2017-07-25
CPC Classifications: F28D,F28F

Claim:
1. A fin for a heat exchanger in which the fin is connected to an outer surface of a heat-exchange object to promote heat exchange between the heat-exchange object and fluid flowing in the vicinity of the heat-exchange object, the fin comprising: a flat portion having a flat shape approximately parallel to a flow direction of the fluid, the flat portion includes an upstream flat part located on an upstream-most end part of the flat portion in the flow direction of the fluid and a downstream flat part located on a downstream-most end part of the flat portion in the flow direction of the fluid; a plurality of louvers cut and inclined from the flat portion, the plurality of louvers being arranged in the flow direction of the fluid; and a fluid-turning part arranged between two of the plurality of louvers adjacent to each other, the fluid-turning part having a flat plate approximately parallel to the flow direction of the fluid, wherein the plurality of louvers are separated into an upstream group located upstream of the fluid-turning part in the flow direction of the fluid, and a downstream group located downstream of the fluid-turning part in the flow direction of the fluid, the louvers of the upstream group are inclined from the flat portion in an inclination direction opposite from an inclination direction in which the louvers of the downstream group are inclined from the flat portion, and wherein at least one of the plurality of the louvers of the upstream group include at least a first set of louvers and a second set of louvers, wherein the first set of louvers consists of all of the louvers immediately downstream of the upstream flat part and immediately upstream of the second set of louvers, and the second set of louvers consist of all the louvers immediately downstream of the first set of louvers and immediately upstream of the fluid-turning part in the fluid flow direction; wherein a first louver in the first set of louvers is directly connected to the upstream flat part; each of the louvers in the first set of louvers is larger in inclination angle from the flat portion than all the louvers in the second set of louvers; or the plurality of the louvers of the downstream group include at least a third set of louvers and a fourth set of louvers, wherein the third set of louvers consists of all of the louvers immediately downstream the fluid-turning part and immediately upstream of the fourth set of louvers, and the fourth set of louvers consist of all the louvers immediately downstream of the third set of louvers and immediately upstream of the downstream flat part in the fluid flow direction, said fourth set of louvers including a last louver that is directly connected to the downstream flat part; wherein each of the louvers in the third set of louvers is smaller in inclination angle from the flat portion than all the louvers in the fourth set of louvers.