Heat exchanger

Abstract

A heat exchanger for preheating the combustion air of a micro-turbine in a cogeneration system is disclosed. The structure of this heat exchanger includes an assembly of flat distribution frames and spacer metal sheets. Each distribution frame is defined by an outline framing a fluid zone and is equipped with inlet orifices and outlet orifices for the passage of this fluid. The metal sheets are supported by support projections at the distribution frames, which simplifies the manufacture of the heat exchanger.

1 . A heat exchanger for an apparatus for the production and/or cogeneration of energy, and comprising:
 a stack of flat distribution frames, each having an internal contour delimiting a hot or cold fluid zone, said fluid zone communicating with inlet orifices and outlet orifices of the fluid, provided in each of the adjacent distribution frames, the hot and cold fluid zones alternating along a thickness of the exchanger;   metal sheets arranged alternately with the distribution frames in the stack to create thermal contact between said fluid zones;   wherein each of the distribution frames is provided with support projections extending from said internal contour towards said fluid zone.   
     
     
         2 . The heat exchanger according to  claim 1 , wherein the projections comprise a plurality of fingers connected to a common base extending into said fluid zone. 
     
     
         3 . The heat exchanger according to  claim 2 , wherein the common base and/or part of each finger is arranged according to a projection of an edge of one of the inlet or outlet orifices of one of the adjacent distribution frames according to the stack. 
     
     
         4 . The heat exchanger according to  claim 2 , wherein the fingers extend at the fluid zone from the common base and in a normal manner with respect to it. 
     
     
         5 . The heat exchanger according to  claim 1 , wherein the distribution frames have substantially polygonal shapes with rectangular inlet and outlet orifices. 
     
     
         6 . The heat exchanger according to  claim 5 , wherein the projections comprise a plurality of parallel fingers of equal length connected to a straight common base extending into said fluid zone. 
     
     
         7 . The heat exchanger according to  claim 6 , wherein a distal end of each finger is arranged according to a projection of an edge of one of the inlet or outlet orifices of one of the adjacent distribution frames according to the stack. 
     
     
         8 . The heat exchanger according to  claim 1 , further comprising a metallic lattice arranged in at least part of the fluid zone. 
     
     
         9 . The heat exchanger according to  claim 1 , wherein each metal sheet has corrugations inclined with respect to a direction of fluid flow at said metal sheet. 
     
     
         10 . The heat exchanger according to  claim 1 , wherein the internal contour of each of the distribution frames comprises alternating convex and concave portions, each of the inlet and outlet orifices being arranged between a convex portion of the internal contour and an external contour of said distribution frame. 
     
     
         11 . The heat exchanger according to  claim 1 , wherein at least one distribution frame comprises inlet and outlet orifices in the form of open slots, each having an edge from which distribution projections extend towards the outside with respect to the fluid zone of said distribution frame. 
     
     
         12 . The heat exchanger according to  claim 11 , wherein the distribution projections are each in the form of a rectilinear segment having a free end at an external contour of one of the adjacent distribution frames in the stack. 
     
     
         13 . The heat exchanger according to  claim 1 , which is cross-flow. 
     
     
         14 . An energy production and/or cogeneration apparatus comprising:
 a combustion chamber;   a turbine arranged to be supplied with combustion gases from the combustion chamber;   a compressor mechanically coupled to the turbine;   a motor-generator mechanically coupled to the turbine and compressor;   the heat exchanger according to  claim 1 ,   wherein the compressor is fluidically coupled to the combustion chamber via the heat exchanger, the latter being arranged to preheat combustion air compressed by the compressor before it is injected into the combustion chamber.   
     
     
         15 . A method of manufacturing a heat exchanger according to  claim 1 , wherein the distribution frames and the metal sheets are assembled by high-temperature vacuum brazing.