Heat exchanger

Abstract

A heat exchanger includes at least two adjacent heat exchanging tubes, each having equilateral triangular cross section. Hot gas flows through the heat exchanging tubes and coolant flows over the heat exchanging tubes. The heat exchanging tubes form a tube bundle of polygonal cross section and have two tube walls arranged in parallel side-by-side relation at a distance to one another.

1 . A heat exchanger, comprising at least two adjacent heat exchanging tubes, each having equilateral triangular cross section, with hot gas flowing through the heat exchanging tubes and coolant flowing over the heat exchanging tubes, said heat exchanging tubes forming a tube bundle of polygonal cross section and having two tube walls arranged in parallel side-by-side relation at a distance to one another. 
     
     
         2 . The heat exchanger of  claim 1 , wherein the heat exchanging tubes are made of steel. 
     
     
         3 . The heat exchanger of  claim 1 , wherein the coolant is cooling water. 
     
     
         4 . The heat exchanger of  claim 1 , further comprising a shell having a rhombic cross section and ensheathing the heat exchanging tubes at a distance thereto. 
     
     
         5 . The heat exchanger of  claim 4 , wherein the shell is made of steel. 
     
     
         6 . The heat exchanger of  claim 4 , wherein the shell has inclined walls, and further comprising bypass tubes extending laterally adjacent to the inclined wails. 
     
     
         7 . The heat exchanger of  claim 6 , further comprising a housing having a rectangular cross section and ensheathing the tube bundle and the bypass tubes. 
     
     
         8 . The heat exchanger of  claim 7 , wherein the housing is made of steel sheet. 
     
     
         9 . The heat exchanger of  claim 1 , further comprising a shell having a hexagonal cross section and ensheathing the heat exchanging tubes at a distance thereto. 
     
     
         10 . The heat exchanger of  claim 9 , wherein the shell is made of steel. 
     
     
         11 . The heat exchanger of  claim 9 , wherein the shell has inclined walls, and further comprising bypass tubes extending laterally adjacent to the inclined walls. 
     
     
         12 . The heat exchanger of  claim 11 , further comprising a housing having a rhombic cross section and ensheathing the tube bundle and the bypass tubes. 
     
     
         13 . The heat exchanger of  claim 12 , wherein the housing is made of steel sheet. 
     
     
         14 . The heat exchanger of  claim 1 , wherein the heat exchanging tubes are provided with protuberances and/or grooves. 
     
     
         15 . The heat exchanger of  claim 14 , wherein the protuberances and/or grooves have a round, half-round, rhomboid, triangular, or oval configuration. 
     
     
         16 . The heat exchanger of  claim 14 , wherein the protuberances and/or grooves extend in longitudinal direction of the heat exchanging tubes or have a helical configuration. 
     
     
         17 . The heat exchanger of  claim 1 , further comprising a turbulence generator inserted in the heat exchanging tubes. 
     
     
         18 . The heat exchanger of  claim 1 , further comprising a tube sheet to combine the heat exchanging tubes to form the tube bundle. 
     
     
         19 . The heat exchanger of  claim 18 , wherein the tube sheet is constructed as a sheet metal water deflector. 
     
     
         20 . The heat exchanger of  claim 1 , forming part of an exhaust gas recirculation system for an internal combustion engine, wherein the hot gas is exhaust gas of the internal combustion engine and the coolant is cooling water.