Heat exchanger, method for producing a heat exchanger and power plant comprising such a heat exchanger

Abstract

A heat exchanger and method for producing such a heat exchanger which during operation in a flow direction is flown through by a medium to be cooled and by two different cooling media. A power plant has a generator cooled by means of a generator cooling gas and a heat exchanger cooling the generator cooling gas.

1 . A heat exchanger, through which a medium to be cooled flows in a flow direction during operation thereof, comprising:
 a first stack of fins having a multitude of first fins stacked in a stacking direction that extends transverse to the flow direction, wherein the first fins are each provided with a multitude of first passage holes that are flush with one another in stacking direction,   at least one further stack of fins arranged adjacent to the first stack of fins in flow direction, and having a multitude of second fins stacked in the stacking direction, wherein the second fins are each provided with a multitude of second passage holes that are flush with one another in stacking direction,   first pipe conduits that extend through the first passage holes of the first fins of the first stack of fins and are press-fitted with the first fins,   second pipe conduits that extend through the second passage holes of the second fins of the at least one further stack of fins and are press-fitted with the second fins, wherein the first pipe conduits and the second pipe conduits are not connected to one another for flow purposes and are provided for passage of a first cooling medium and a second cooling medium, wherein the first and second cooling media are different from one another, and   at least one cover that connects the first stack of fins and the at least one further stack of fins to one another, which is placed atop an outer first fin of the first stack of fins and atop the adjacent outer second fin of the at least one further stack of fins and covers these fins, wherein the at least one cover has been provided with first passage holes arranged and formed so as to correspond to the first passage holes of the first fins of the first stack of fins, through which the first pipe conduits are guided, and has been provided with second passage holes arranged and formed so as to correspond to the second passage holes of the second fins of the at least one further stack of fins, through which the second pipe conduits are guided.   
     
     
         2 . The heat exchanger as claimed in  claim 1 ,
 wherein the first fins have a greater area than the second fins.   
     
     
         3 . The heat exchanger as claimed in  claim 1 ,
 wherein the design of the surface of the first fins is different than the design of the surface of the second fins.   
     
     
         4 . The heat exchanger as claimed in  claim 1 ,
 wherein the first fins and the second fins are produced from sheet material.   
     
     
         5 . The heat exchanger as claimed in  claim 1 ,
 wherein a distance between the first fins in stacking direction is different than the distance between the second fins in stacking direction, preferably greater.   
     
     
         6 . The heat exchanger as claimed in  claim 1 ,
 wherein the first fins and the second fins have been produced from a sheet material having a coating on one or both sides.   
     
     
         7 . The heat exchanger as claimed in  claim 1 ,
 wherein the first pipe conduits are each connected to one another via U-shaped connecting conduits, and the first cooling medium flows through them successively, and/or   wherein the second pipe conduits are each connected to one another by U-shaped connecting conduits, and the second cooling medium flows through them successively.   
     
     
         8 . The heat exchanger as claimed in  claim 1 ,
 wherein the flow cross section of the first pipe conduits is different than the flow cross section of the second pipe conduits.   
     
     
         9 . The heat exchanger as claimed in  claim 1 ,
 wherein the first pipe conduits and the second pipe conduits have been manufactured from a metallic material.   
     
     
         10 . The heat exchanger as claimed in  claim 1 ,
 wherein the inner faces of the first pipe conduits and/or the inner faces of the second pipe conduits are structured.   
     
     
         11 . The heat exchanger as claimed in  claim 1 ,
 wherein an arrangement pattern of the first passage holes is different than the arrangement pattern of the second passage holes.   
     
     
         12 . The heat exchanger as claimed in  claim 1 ,
 wherein the at least one cover has been produced from a metallic material, and/or from a metal sheet.   
     
     
         13 . The heat exchanger as claimed in  claim 1 ,
 wherein the at least one cover encompasses the first stack of fins and the at least one further stack of fins on opposite sides.   
     
     
         14 . The heat exchanger as claimed in  claim 1 ,
 wherein the first stack of fins and the at least one further stack of fins are connected to one another by at least one strut.   
     
     
         15 . A process for producing a heat exchanger as claimed in  claim 1 ,
 wherein the first fins and the second fins are produced simultaneously in a single fin compression device.   
     
     
         16 . The process as claimed in  claim 15 ,
 wherein the first pipe conduits and the second pipe conduits are expanded simultaneously in a pipe conduit expansion machine.   
     
     
         17 . A power plant comprising:
 a generator cooled by means of a generator cooling gas, and   a heat exchanger as claimed in  claim 1  that cools the generator cooling gas.   
     
     
         18 . The power plant as claimed in  claim 17 ,
 wherein the first cooling medium that flows through the heat exchanger is cooling water and the second cooling medium that flows through the heat exchanger is a coolant.   
     
     
         19 . The heat exchanger as claimed in  claim 5 ,
 wherein the distance between the first fins in stacking direction is greater than the distance between the second fins in stacking direction.   
     
     
         20 . The heat exchanger as claimed in  claim 8 ,
 wherein the flow cross section of the first pipe conduits is greater than the flow cross section of the second pipe conduits.   
     
     
         21 . The heat exchanger as claimed in  claim 9 ,
 wherein the metallic material comprises copper.