Louvred fins for heat exchangers

in a heat exchanger of the tube and fin core or plate-fin separator type including at least one row of flat tubes and wherein the fins are provided with louvres extending longitudinally parallel to the row of tubes and have an overhanging portion beyond the row of tubes, the improvement comprising progressively longitudinally shortened louvres formed in the overhanging portion from adjacent the outer edge thereof to a point substantially aligned with the edges of the row of tubes, in which the length of the louvre adjacent the outer edge of the fin is slightly shorter than the length of the normal louvres located between adjacent tubes in a row, and a second louvre shorter in length than said outer louvre is positioned between the normal louvres and said outer louvre.

In a heat exchanger of the tube and fin core or plate-fin separator type including at least one row of tubes and wherein the fins are provided with louvres extending longitudinally parallel to the row of tubes and have an overhanging portion beyond the row of tubes, the improvement comprising progressively longitudinally shortened louvres formed in the overhanging portion of the fin from the outer edge thereof to a point substantially aligned with the edges of the row of tubes, the length of the louvre adjacent the outer edge of the fin being slightly shorter than the length of the normal louvres located between adjacent tubes in a row, a second louvre adjacent to and shorter in length than the outer louvre, and a third louvre located between said second louvre and the normal louvres and shorter in length than said second louvre.

In a heat exchanger of the tube and fin or plate-fin separator type wherein the fins are provided with louvres and have an overhanging portion extending beyond the rows of tubes, the improvement comprising that all louvres except the louvre at the leading and/or trailing edge of the fin are oriented at an identical acute angle to the fin surface and the louvre at the leading end/or trailing edge of the fin is oriented substantially parallel to the fin surface and to the direction of bulk air flow through the fins.

In a heat exchanger of the tube and fin or plate-fin separator type wherein the fins are provided with louvres and have an overhanging portion extending beyond the rows of tubes, the improvement comprising that all louvres except the louvre at the leading and/or trailing edge of the fin are oriented at an identical angle to the fin surface and the louvre at the leading and/or trailing edge of the fin is formed substantially parallel to the fin surface and to the direction of bulk air flow through the fins, an elongated opening defining the edge of the louvre at the leading and/or trailing edge of the fin.