High strength fin louver design

Abstract

Heat exchanger assemblies of increased strength are provided having louvered fins that achieve both high thermal efficiency and high strength simultaneously. By providing for a three-piece louvered fin, tube-fin heat exchangers having at least one three-piece single louver block, and, in particular, a streamlined inclined three-piece single louver block, exhibit fins with superior characteristics and overall strength for heat exchanger assembly of louvered fin design, with reduced areas or zones of boundary layer air.

1 . A tube-fin automotive heat exchanger comprising:
 a. a plurality of tubes running basically parallel to one another;   b. a plurality of fins having at least one block of louvers, the plurality of fins running between the tubes and being basically coplanar relative to the tubes;   c. at least one end tank connected to the tubes;   
     wherein the block of louvers comprises a set of louvers having at least one three-piece single louver having two half louver sections and one flat area louver section. 
   
   
       2 . A tube-fin automotive heat exchanger, as in  claim 1 , having at least one first end tank and at least one second end tank opposite the at least one first end tank, wherein one end of the plurality of tubes is connected to and in fluid communication with the one first end tank and wherein the other end of the plurality of tubes is connected to and in fluid communication with the at least one second end tank. 
   
   
       3 . A tube-fin automotive heat exchanger, as in  claim 2 , having at least two blocks of louvers. 
   
   
       4 . A tube-fin automotive heat exchanger, as in  claim 2 , wherein the at least two blocks of louvers are symmetric around an axis perpendicular to the width of the fin. 
   
   
       5 . A tube-fin automotive heat exchanger, as in  claim 4 , wherein the one three-piece single louver is a streamlined inclined three-piece single louver. 
   
   
       6 . A tube-fin automotive heat exchanger, as in  claim 5 , having at least one non-three piece louver. 
   
   
       7 . A tube-fin automotive heat exchanger, as in  claim 6 , wherein the streamlined inclined three-piece single louver is an integral inclined three-piece single louver and the half louvers of the three-piece single louver have angles of inclination of similar to or identical with at least one of the non-three piece louvers. 
   
   
       8 . A tube-fin automotive heat exchanger, as in  claim 7 , wherein all the louvers in at least one block of louvers have an angle (alpha) with a center plane axis of the length of the fin that is similar or identical with each other within that block. 
   
   
       9 . A tube-fin automotive heat exchanger, as in  claim 8 , wherein the louvers in each block have angles (alpha) with the center plane axis of the length of the fin that are similar or identical with each other within each respective block. 
   
   
       10 . A tube-fin automotive heat exchanger, as in  claim 6 , wherein at least one block of louvers has a plurality of three-piece single louvers and non three-piece louvers along the fin, wherein the flat area sections of the three-piece single louvers have an average ratio of width of flat area sections to width of non three-piece louvers of between about 0.10 and 0.90. 
   
   
       11 . A tube-fin automotive heat exchanger, as in  claim 10 , wherein the flat area sections of the three-piece single louvers have an average ratio of width of flat area sections to width of non three-piece louvers of between about 0.30 and 0.70. 
   
   
       12 . A tube-fin automotive heat exchanger, as in  claim 6 , wherein the relative difference between the width of two half louver sections of the three-piece single louver and the width of half of the a non-three piece louver is less than ⅓. 
   
   
       13 . A tube-fin automotive heat exchanger, as in  claim 6 , wherein the gauge of the fin is 0.10 mm or less. 
   
   
       14 . A tube-fin automotive heat exchanger, as in  claim 7 , wherein the gauge of the fin is 0.10 mm or less and wherein the inclination of the two half louver sections is within a range of about α±⅓α, where a is the average inclination of non three-piece louvers. 
   
   
       15 . A tube-fin automotive heat exchanger, as in  claim 6 , wherein at least two of the plurality of tubes are folded tubes in a row that have a joint at the fold area and at least one three-piece single louver is located adjacent to or immediately across from, the area of the joint location of the folded tube. 
   
   
       16 . A tube-fin automotive heat exchanger, as in  claim 7 , wherein at least two of the plurality of tubes are folded tubes in a row that have a joint at the fold area and at least one three-piece single louver is located adjacent to or immediately across from, the area of the joint location of the folded tube. 
   
   
       17 . A tube-fin automotive heat exchanger as in  claim 6 , wherein at least two of the plurality of tubes are folded tubes in a row that have a joint at the fold area and the at least one block of louvers is located adjacent to or immediately across from, the area of the joint location of the folded tube. 
   
   
       18 . A tube-fin automotive heat exchanger as in  claim 17 , wherein the fin height changes across the length of the block of louvers and wherein the fin height is at its highest at the location of the three-piece single louver. 
   
   
       19 . A fin system for a heat exchanger having louvers to enhance transfer of heat from a first medium to a second medium, comprising at least two blocks of louvers, each block having at least one set of louvers per block, and each block having at least one set of louvers having at least one three piece single louver and at least one non three-piece louver. 
   
   
       20 . A fin system, as in  claim 19 , wherein at least one block of louvers comprises a plurality of non three-piece louvers and a plurality of three-piece single louvers, and wherein the average length of the non-three piece louvers is approximately equal to the average length of the three-piece single louvers.