Heat exchanger

Abstract

The invention relates to a heat exchanger with a channel ( 4 ) through which cooling agent flows and a channel ( 3 ) through which fluid to be cooled flows, whereby ribs ( 6 ) project into at least one of the channels ( 3, 4 ). According to the invention, these ribs ( 6 ) feature a linear approach edge ( 11 ) and a linear flow-off edge ( 15 ), whereby the side walls ( 12 ) run continuously between the approach edge ( 11 ) and the flow-off edge ( 15 ). By these means it is achieved that a turbulent boundary layer forms at the ribs, which boundary layer ends in a turbulent eddy in the area of the flow-off edge ( 15 ). This leads to an increased efficiency of the heat exchanger and simultaneously to a good homogenization of the fluid. Moreover, sooting is reliably avoided.

1 . A heat exchanger comprising: 
 a channel through which cooling agent flows; and    a channel through which fluid to be cooled flows, wherein channels are separated from one another by a wall from which issue ribs extending into at least one of the two channels, wherein each rib includes one linear approach edge and two linear flow-off edges, whereby the approach edge and the two flow-off edges delimit two continuously running side walls of the ribs.    
   
   
       2 . A heat exchanger according to  claim 1 , wherein the ribs extend along a main flow direction.  
   
   
       3 . A heat exchanger according to  claim 1 , wherein the side walls of each rib adjacent to the approach edge and the flow-off edges enclose an angle to one another that is less than or equal to 90°.  
   
   
       4 . A heat exchanger according to  claim 3 , wherein in a front area, the side walls extending from the approach edge of each rib are arranged essentially wedge-shaped with respect to one another.  
   
   
       5 . A heat exchanger according to  claim 1 , wherein in a front area, an angle between tangents to the two side walls decreases continuously in a main flow direction until the side walls run parallel to one another in a back area.  
   
   
       6 . A heat exchanger according to  claim 1 , wherein the ribs are arranged in rows adjacent to one another perpendicular to a main flow direction, whereby the ribs of each row are arranged staggered with respect to the following row.  
   
   
       7 . A heat exchanger according to  claim 1 , wherein the heat exchanger is an exhaust gas heat exchanger whose ribs project into the channel through which fluid to be cooled flows conducting exhaust gas.  
   
   
       8 . A heat exchanger according to  claim 2 , wherein the side walls of each rib adjacent to the approach edge and the flow-off edges enclose an angle to one another that is less than or equal to 90°.  
   
   
       9 . A heat exchanger according to  claim 2 , wherein in a front area, an angle between tangents to the two side walls decreases continuously in the main flow direction until the side walls run parallel to one another in a back area.  
   
   
       10 . A heat exchanger according to  claim 2 , wherein the ribs are arranged in rows adjacent to one another perpendicular to the main flow direction, whereby the ribs of each row are arranged staggered with respect to the following row.  
   
   
       11 . A heat exchanger according to  claim 3 , wherein the ribs are arranged in rows adjacent to one another perpendicular to a main flow direction, whereby the ribs of each row are arranged staggered with respect to the following row.  
   
   
       12 . A heat exchanger according to  claim 4 , wherein the ribs are arranged in rows adjacent to one another perpendicular to a main flow direction, whereby the ribs of each row are arranged staggered with respect to the following row.  
   
   
       13 . A heat exchanger according to  claim 5 , wherein the ribs are arranged in rows adjacent to one another perpendicular to a main flow direction, whereby the ribs of each row are arranged staggered with respect to the following row.