Tube for a heat exchanger

Abstract

The present invention relates to a tube for a heat exchanger comprising a region with dimples according to a specific pattern such that it increases the degree of heat exchange with low pressure drop. The use of a tube for a heat exchanger according to the invention in heat exchangers for EGR (Exhaust Gas Recirculation) systems is of particular interest. The present invention is also considered of interest for the environment as it increases the efficiency of the heat exchangers for which it is designed.

1 . A tube for a heat exchanger having a flattened configuration comprising a first essentially planar face and a second essentially planar face parallel to and spaced from the first face; both faces being connected by side walls where at least one face has a plurality of dimples configured according to a pattern that is repeated along the longitudinal direction X-X′ of the tube, where this pattern is configured by means of a plurality of groups of dimple alignments covering the width of the planar face, aligned according to one and the same direction Y-Y′ arranged obliquely between 40° and 50° degrees with respect to the longitudinal direction X-X′, and where it at least comprises:
 a first group which is formed by two dimples, a first elongated dimple extending according to the oblique direction Y-Y′ aligned with a first point dimple such that a first flow channel is established between the elongated dimple and the point dimple, 
 a second group which is formed by four point dimples, a second point dimple, a third point dimple, a fourth point dimple and a fifth point dimple, essentially aligned according to the oblique direction Y-Y′, such that a second flow channel is established between the second point dimple and the third point dimple, a third flow channel is established between the third point dimple and the fourth point dimple, a fourth flow channel is established between the fourth point dimple and the fifth point dimple, 
 a third group which is formed by two dimples, a sixth point dimple aligned with a second elongated dimple, extending according to the oblique direction Y-Y′, such that a fifth flow channel is established between the sixth point dimple and the second elongated dimple, 
 a fourth group which is formed by four point dimples, a seventh dimple, an eighth dimple, a ninth dimple and a tenth dimple, essentially aligned according to the oblique direction Y-Y′, such that a sixth flow channel is established between the seventh point dimple and the eighth point dimple, a seventh flow channel is established between the eighth point dimple and the ninth point dimple, an eighth flow channel is established between the ninth point dimple and the tenth point dimple, 
 
       where the position of the first flow channel is such that the flow going through same in the operating mode is mainly transported towards the third flow channel and the fourth flow channel. 
     
     
         2 . The tube according to  claim 1 , where in the second group formed by four point dimples essentially aligned according to the oblique direction Y-Y′, the first pair of dimples formed by the second point dimple and third point dimple is aligned according to the oblique direction Y-Y′, the second pair of dimples formed by the fourth point dimple and the fifth point dimple is aligned according to the oblique direction Y-Y′; and the alignment of the first pair and the alignment of the second pair are misaligned a specific distance despite being parallel. 
     
     
         3 . The tube according to  claim 1 , where in the fourth group formed by four point dimples essentially aligned according to the oblique direction Y-Y′, the first pair of dimples formed by the seventh dimple and the eighth dimple is aligned according to the oblique direction Y-Y′, the second pair of dimples formed by the ninth dimple and the tenth dimple is aligned according to the oblique direction Y-Y′; and the alignment of the first pair and the alignment of the second pair are misaligned despite being parallel. 
     
     
         4 . The tube according to  claim 1 , where the first flow channel, the third flow channel and the fifth flow channel are essentially aligned. 
     
     
         5 . The tube according to  claim 1 , where the first flow channel, the fourth flow channel and the eighth flow channel are essentially aligned. 
     
     
         6 . The tube according to  claim 1 , where the second flow channel, the fifth flow channel and the sixth flow channel are essentially aligned. 
     
     
         7 . The tube according to  claim 1 , where the second point dimple, the fifth point dimple, the seventh point dimple and the tenth point dimple are widened in the direction transverse to the oblique direction Y-Y′. 
     
     
         8 . The tube according to  claim 1 , where the tube has one and the same pattern on the first face and the second face. 
     
     
         9 . The tube according to  claim 1 , where it comprises on a first flattened face one or more patterns distributed along the length of the tube and comprises on a second flattened face, the opposite face, one or more patterns distributed along the length of the tube, and where
 the pattern of the first face and the pattern of the second face are distributed longitudinally such that they extend with the same length,   the pattern of the first face and the pattern of the second face are positioned such that the end of the first elongated dimple located closest to the central axis of the tube of the first face and the end of the second elongated dimple located closest to the central axis of the tube of the second face overlap one another according to a projection on a plane parallel to both faces.   
     
     
         10 . A heat exchanger comprising at least one tube, the tube having a flattened configuration comprising a first essentially planar face and a second essentially planar face parallel to and spaced from the first face; both faces being connected by side walls where at least one face has a plurality of dimples configured according to a pattern that is repeated along the longitudinal direction X-X′ of the tube, where this pattern is configured by means of a plurality of groups of dimple alignments covering the width of the planar face, aligned according to one and the same direction Y-Y′ arranged obliquely between 40° and 50° degrees with respect to the longitudinal direction X-X′, and where it at least comprises:
 a first group which is formed by two dimples, a first elongated dimple extending according to the oblique direction Y-Y′ aligned with a first point dimple such that a first flow channel is established between the elongated dimple and the point dimple, 
 a second group which is formed by four point dimples, a second point dimple, a third point dimple, a fourth point dimple and a fifth point dimple, essentially aligned according to the oblique direction Y-Y′, such that a second flow channel is established between the second point dimple and the third point dimple, a third flow channel is established between the third point dimple and the fourth point dimple, a fourth flow channel is established between the fourth point dimple and the fifth point dimple, 
 a third group which is formed by two dimples, a sixth point dimple aligned with a second elongated dimple, extending according to the oblique direction Y-Y′, such that a fifth flow channel is established between the sixth point dimple and the second elongated dimple, 
 a fourth group which is formed by four point dimples, a seventh dimple, an eighth dimple, a ninth dimple and a tenth dimple, essentially aligned according to the oblique direction Y-Y′, such that a sixth flow channel is established between the seventh point dimple and the eighth point dimple, a seventh flow channel is established between the eighth point dimple and the ninth point dimple, an eighth flow channel is established between the ninth point dimple and the tenth point dimple, 
 
       where the position of the first flow channel is such that the flow going through same in the operating mode is mainly transported towards the third flow channel and the fourth flow channel.