Heat exchanger comprising a core of tubes

Abstract

The invention concerns a heat exchanger ( 1 ) comprising an inlet tank ( 2 ), having a fluid inlet ( 4 ),and an outlet tank ( 3 ), having a fluid outlet ( 5 ),and a core ( 6 ) of tubes ( 7, 8 ) joining said inlet tank ( 2 ) and said outlet tank ( 3 ) together and creating a plurality of fluid flow paths (P 1 ) from said inlet tank ( 2 ) to said outlet tank ( 3 ), wherein said tubes ( 7, 8 ) belong to a primary and a secondary group of tubes( 7, 8 ). According to the invention said inlet tank ( 2 ) and said outlet tank ( 3 ) have header plates( 9, 10 ), which form core interfaces and comprise throughout identical tube insertion orifices for both the primary group of tubes ( 7 ) and the secondary group of tubes ( 8 ).Further, the tubes being a member of the primary group are base tubes ( 7 )and the tubes being a member of the secondary group are adaptation tubes ( 8 ), which differ from the base tubes ( 7 ) and a reused to locally change properties of the heat exchanger ( 1 ) in critical areas of the heat exchanger ( 1 ).

1 . A heat exchanger comprising one inlet tank, having a fluid inlet for a fluid, and one outlet tank, having a fluid outlet for said fluid, and a core of tubes joining said one inlet tank and said one outlet tank together and creating a plurality of fluid flow paths for said fluid from said one inlet tank to said one outlet tank, wherein said tubes belong to a primary and a secondary group of tubes,
 wherein said one inlet tank comprises a first header plate, which forms a core interface of said one inlet tank,   wherein said one outlet tank comprises a second header plate, which forms a core interface of said one outlet tank,   wherein said first and second header plates comprise throughout identical tube insertion orifices for both the primary group of tubes and the secondary group of tubes, and   wherein the tubes being a member of the primary group are base tubes, and the tubes being a member of the secondary group are adaptation tubes, which are designed differently than the base tubes of the primary group and are used to locally change properties of the heat exchanger in critical areas of the heat exchanger.   
     
     
         2 . The heat exchanger according to  claim 1 , wherein said secondary group in order to prolong life of the heat exchanger comprises adaptation tubes each providing an enhanced strength compared to a basic strength provided by each one of said base tubes, wherein said adaptation tubes are used in areas of the heat exchanger where stress levels tend to be higher than a medium stress level of the entire heat exchanger. 
     
     
         3 . The heat exchanger according to  claim 2 , wherein said adaptation tubes provide an enhanced strength by having a wall thickness exceeding a wall thickness of the base tubes. 
     
     
         4 . The heat exchanger according to  claim 2 , wherein said adaptation tubes provide an enhanced strength by comprising stiffening inserts arranged in tube openings. 
     
     
         5 . The heat exchanger according to  claim 2 , wherein said adaptation tubes provide an enhanced strength by comprising first turbulators that are stiffer than second turbulators arranged in said base tubes. 
     
     
         6 . The heat exchanger according to  claim 2 , wherein said adaptation tubes provide an enhanced strength by comprising internal stiffening ribs. 
     
     
         7 . The heat exchanger according to  claim 2 , wherein said adaptation tubes provide an enhanced strength by comprising extra durable tube seams created by all smooth tube walls. 
     
     
         8 . The heat exchanger according to  claim 2 , wherein said heat exchanger comprises a first row of tubes and a second row of tubes, and wherein at least a plurality of the tubes of the first row belong to the primary group of tubes and all tubes of the second row belong to the secondary group of tubes. 
     
     
         9 . The heat exchanger according to  claim 1 , wherein said secondary group in order to improve efficiency of the heat exchanger comprises adaptation tubes, each providing a first flow resistance that is lower than a second flow resistance provided by each one of said base tubes, wherein said adaptation tubes are arranged in areas of the heat exchanger where fluid flow levels tend to be lower than a medium fluid flow level of the entire heat exchanger. 
     
     
         10 . The heat exchanger according to  claim 9 , wherein said adaptation tubes provide a lower flow resistance by comprising first turbulators that cause a lower flow resistance than second turbulators being arranged in said base tubes. 
     
     
         11 . The heat exchanger according to  claim 9 , wherein said adaptation tubes provide a lower flow resistance by having all smooth walls, while said base tubes have dimpled walls. 
     
     
         12 . The heat exchanger according to  claim 9 , wherein said heat exchanger comprises a first row of tubes and a second row of tubes, and wherein all tubes of the first row belong to the secondary group of tubes and all tubes of the second row belong to the primary group of tubes. 
     
     
         13 . The heat exchanger according to  claim 1 , wherein said secondary group comprises adaptation tubes, each providing a lower flow resistance than a flow resistance provided by each one of said base tubes, wherein said adaptation tubes are arranged in the heat exchanger in an alternating pattern mixed with base tubes. 
     
     
         14 . The heat exchanger according to  claim 13 , wherein said adaptation tubes provide a lower flow resistance by comprising first turbulators that cause a lower flow resistance than second turbulators being arranged in said base tubes. 
     
     
         15 . The heat exchanger according to  claim 13 , wherein said adaptation tubes provide a lower flow resistance by having all smooth walls, while said base tubes have dimpled walls. 
     
     
         16 . The heat exchanger according to  claim 13 , wherein said alternating pattern comprises a row of alternatingly a base tube and an adaptation tube. 
     
     
         17 . The heat exchanger according to  claim 13 , wherein said alternating pattern comprises a row of alternatingly two base tubes and an adaptation tube. 
     
     
         18 . The heat exchanger according to  claim 1 , wherein said secondary group of tubes is subdivided into at least two kinds of differently designed tubes.