Heat Exchanger

Abstract

A compact heat exchanger is formed from a plurality of very thin layers that are affixed to one another and that are formed via additive manufacturing. Such additive manufacturing enables the configurations of the heat exchanger's flow channels and the arrangements of such flow channels to be optimized for improved heat transfer performance, for improved resistance to thermal and mechanical stresses, and for optimization based upon other factors such as the environment in which the heat exchanger will be situated.

What is claimed is: 
     
         1 . A compact heat exchanger comprising:
 a plurality of layers affixed to one another and together forming a core and a header apparatus;   the core having formed therein a plurality of channels, the plurality of channels comprising a number of first channels and a number of second channels, at least a portion of the number of first channels being position for being in heat transfer relation with at least a portion of the number of second channels;   the header apparatus comprising at least a first header that is in fluid communication with at least some of the channels of the number of channels;   the at least first header having a channel end and a connection end, the channel end being situated adjacent the core and including a number of flow connections that are in direct fluid communication with the at least some of the channels, the connection end having an opening that is structured to be connected in fluid communication with another flow structure, the at least one header comprising a flow passage that extends between the channel end and connection end and that enables fluid communication between the number of flow connections and the opening; and   at least one of the layers of the plurality of layers being at least one of:
 a layer that comprises a portion of but less than the entirety of the at least first header and that has formed therein at least a portion of the flow passage, 
 a layer that comprises at least a portion of the core having formed therein at least a portion of a first channel and at least a portion of a second channel that are fluidly isolated from one another, and 
 a layer that comprises at least a portion of the core having formed therein at least a portion of a channel of the plurality of channels and that further comprises a portion of the at least first header and that has formed therein at least a portion of the flow passage. 
   
     
     
         2 . The compact heat exchanger of  claim 1  wherein at least some of the channels of the plurality of channels each have an arcuate perimeter that is of a shape that is non-circular. 
     
     
         3 . The compact heat exchanger of  claim 2  wherein another channel that is situated adjacent a channel of the at least some of the channels has another arcuate perimeter that is of another shape different than the shape. 
     
     
         4 . The compact heat exchanger of  claim 1  wherein the number of first channels are in fluid communication with one another and wherein the number of second channels are in fluid communication with one another, the number of first channels being fluidly isolated from the number of second channels, and wherein at least one first channel of the number of first channels is situated adjacent at least three other first channels of the number of first channels and is further situated adjacent at least three second channels of the number of second channels. 
     
     
         5 . The compact heat exchanger of  claim 1  wherein the core comprises a wall having situated at a side thereof both a first channel of the number of first channels and a second channel of the number of second channels and having at another side thereof a wall surface that faces generally away from the number of first channels and the number of second channels, the minimum thickness of the wall between the wall surface and the first channel being different than the minimum thickness of the wall between the wall surface and the second channel. 
     
     
         6 . The compact heat exchanger of  claim 1  wherein the core comprises a plurality of core portions affixed together, at least some of the core portions of the plurality of core portions each having formed therein a plurality of channel portions, the plurality of channels portions comprising a number of first channel portions and a number of second channel portions, a first channel portion of the number of first channel portions of each of a plurality quantity of the plurality of core portions being connected together end-to-end to form at least a portion of a first channel of the number of first channels, a second channel portion of the number of second channel portions of each of the plurality quantity of the plurality of core portions being connected together end-to-end to form at least a portion of a second channel of the number of second channels. 
     
     
         7 . The compact heat exchanger of  claim 1  wherein the at least first header comprises a number of flow directors, and wherein a flow passage of the number of flow passages comprises a plurality of flow passage portions that together extend between the opening and a corresponding channel of the at least some of the channels and that permit fluid flow therebetween, at least a first flow director of the number of flow directors being situated adjacent the core and between a pair of first channels of the number of first channels, the at least first flow director having an external surface, a portion of the external surface forming at least a part of a flow passage portion of the plurality of flow passage portions that is in fluid communication with a first channel of the pair of first channels 
     
     
         8 . The compact heat exchanger of  claim 7  wherein another portion of the external surface forms at least a part of another flow passage portion of the plurality of flow passage portions of another flow passage of the number of flow passages that is in direct fluid communication with another first channel of the pair of first channels. 
     
     
         9 . The compact heat exchanger of  claim 1  wherein the at least first header is a first inlet header, and wherein the header apparatus further comprises a first outlet header;
 the first inlet header being in fluid communication with at least some of the number of first channels at an inlet end thereof; 
 the first outlet header being in fluid communication with the at least some of the number of first channels at an outlet end thereof; and 
 the at least one of the layers being a layer that comprises a portion of the core having formed therein at least a portion of a first channel of the number of first channels, and that further comprises a portion of the first inlet header and a portion of the first outlet header in fluid communication with the at least portion of the first channel. 
 
     
     
         10 . The compact heat exchanger of  claim 9  wherein the header apparatus further comprises a second inlet header and a second outlet header, the second inlet header being in fluid communication with at least some of the number of second channels at an inlet end thereof, and the second outlet header being in fluid communication with the at least some of the number of first channels at an outlet end thereof. 
     
     
         11 . The compact heat exchanger of  claim 1  wherein at least some of the channels of the plurality of channels are elongated along a direction of elongation and include a number of undulations along the direction of elongation. 
     
     
         12 . The compact heat exchanger of  claim 1  wherein the core comprises a wall that is situated between a pair of adjacent channels of the plurality of channels, wherein the wall is of a thickness at a location on the core whereby the pair of adjacent channels are separated apart by a distance that is equal to the thickness, and wherein the wall is of another thickness at another location on the core spaced from the location whereby the pair of adjacent channels are separated apart by another distance that is equal to the another thickness, the thickness and the another thickness being unequal. 
     
     
         13 . The compact heat exchanger of  claim 1  wherein the number of first channels are in fluid communication with one another, wherein the number of second channels are in fluid communication with one another, and wherein the plurality of channels further comprise a number of additional channels that are fluidly isolated from the number of first channels and that are fluidly isolated from the number of second channels. 
     
     
         14 . The compact heat exchanger of  claim 13  wherein the number of additional channels comprise an additional channel that is situated adjacent at least one of a first channel of the number of first channels and a second channel of the number of second channels. 
     
     
         15 . The compact heat exchanger of  claim 14  wherein the core has formed therein an opening that extends between the additional channel and the exterior of the core. 
     
     
         16 . The compact heat exchanger of  claim 14  wherein the additional channel is situated adjacent a plurality of first channels of the number of first channels and is further situated adjacent a plurality of second channels of the number of second channels. 
     
     
         17 . The compact heat exchanger of  claim 13  wherein the core further comprises a number of heaters that are received in the number of additional channels and that are structured to be operable to preheat the compact heat exchanger.