Microchannel heat exchanger and methods of manufacture

Abstract

An apparatus includes a first flow panel and a second flow panel. The first flow panel includes a first flow portion and a second flow portion. The first flow portion defines a flow passageway within which a gas can flow in a first direction. The second flow portion defines a set of microchannels in fluid communication with the flow passageway and within which the gas can flow in a second direction, where the second direction is nonparallel to the first direction. The first flow panel is coupled to the second flow panel to define a heat transfer passageway within which a heat transfer medium can be conveyed in a third direction, where the third direction is opposite the first direction. In such embodiments, the heat transfer passageway is fluidically isolated from the flow passageway and the set of microchannels by a thermally conductive side wall.

What is claimed is: 
     
         1 . An apparatus, comprising:
 a first flow panel including a first flow portion and a second flow portion, the first flow portion defining a flow passageway within which a gas can flow in a first direction, the second flow portion defining a plurality of microchannels in fluid communication with the flow passageway and within which the gas can flow in a second direction, the second direction being nonparallel to the first direction,   the first flow panel coupled to a second flow panel to define a heat transfer passageway within which a heat transfer medium can be conveyed in a third direction, the third direction opposite the first direction, the heat transfer passageway fluidically isolated from the flow passageway and the plurality of microchannels by a thermally conductive side wall.   
     
     
         2 . The apparatus of  claim 1 , wherein the first flow portion includes a plurality of flow structures within the flow passageway. 
     
     
         3 . The apparatus of  claim 1 , wherein the first flow portion includes a plurality of flow structures within the flow passageway, the plurality of flow structures configured to produce a spatially uniform flow within the flow passageway. 
     
     
         4 . The apparatus of  claim 1 , wherein:
 the first flow panel defines a first opening through which a first portion of the gas can flow into the flow passageway in the first direction; and   the first flow panel defines a second opening through which a second portion of the gas can flow into the flow passageway in a fourth direction, the fourth direction opposite the first direction.   
     
     
         5 . The apparatus of  claim 1 , wherein:
 the first flow portion is an inlet flow portion;   the flow passageway is an inlet flow passageway; and   the first flow panel including a flow outlet portion defining a flow outlet passageway in fluid communication with the plurality of microchannels and within which the gas can flow in a fourth direction, the fourth direction opposite the first direction.   
     
     
         6 . The apparatus of  claim 1 , wherein the second direction is substantially normal to the first direction. 
     
     
         7 . The apparatus of  claim 1 , wherein the first flow panel and the second flow panel are configured such that the heat transfer passageway is substantially linear. 
     
     
         8 . The apparatus of  claim 1 , wherein the first flow panel is planar such that a cross-sectional shape of the heat transfer passageway is substantially rectangular. 
     
     
         9 . The apparatus of  claim 1 , wherein each of the plurality of microchannels defines a hydraulic diameter of between about 10 microns and about 200 microns. 
     
     
         10 . An apparatus, comprising:
 a first flow panel including a base member, a first cover and a second cover, a first surface of the base member defining a first plurality of microchannels within which a first portion of a gas can flow in a first direction, a second surface of the base member defining a second plurality of microchannels within which a second portion of the gas can flow in a first direction, the first cover coupled to the first surface to form a boundary for the first plurality of microchannels, the second cover coupled to the second surface to form a boundary for the second plurality of microchannels,   the first flow panel coupled to a second flow panel to define a first heat transfer passageway between the first cover of the first flow panel and a cover of the second flow panel, within which a heat transfer medium can be conveyed in a second direction, the second direction opposite the first direction,   the first flow panel coupled to a third flow panel to define a second heat transfer passageway between the second cover of the first flow panel and a cover of the second flow panel, within which the heat transfer medium can be conveyed in the second direction.   
     
     
         11 . The apparatus of  claim 10 , wherein the first flow panel includes a first flow portion and a second flow portion, the first flow portion defining a flow passageway within which the first portion of the gas and the second portion of the gas can flow in a third direction, the third direction nonparallel to the first direction, the second flow portion defining the first plurality of microchannels and the second plurality of microchannels. 
     
     
         12 . The apparatus of  claim 11 , wherein the first flow portion includes a plurality of flow structures within the flow passageway, the plurality of flow structures configured to produce a uniform flow between at least one of the first plurality of microchannels or the second plurality of microchannels. 
     
     
         13 . The apparatus of  claim 11 , wherein the third direction is substantially normal to the first direction. 
     
     
         14 . The apparatus of  claim 10 , wherein the first flow panel and the second flow panel are configured such that the first heat transfer passageway is substantially linear. 
     
     
         15 . The apparatus of  claim 10 , wherein the first flow panel is planar such that a cross-sectional shape of the heat transfer passageway is substantially rectangular. 
     
     
         16 . A method, comprising:
 producing a flow passageway in a first portion of a base member, the flow passageway defining a first direction of flow;   producing a plurality of microchannels in a second portion of the base member such that each of the plurality of microchannels is in fluid communication with the flow passageway, the plurality of microchannels defining a second direction of flow being nonparallel to the first direction of flow;   coupling a cover to the base member to form a first flow panel;   coupling the first flow panel to a second flow panel to define a heat transfer passageway within which a heat transfer medium can be conveyed in a third direction, the third direction opposite the first direction of flow, the heat transfer passageway fluidically isolated from the flow passageway and the plurality of microchannels by the cover.   
     
     
         17 . The method of  claim 16 , wherein the producing the flow passageway and the producing the plurality of microchannels includes electrochemically etching the base member. 
     
     
         18 . The method of  claim 16 , wherein the base member is a substantially planar member. 
     
     
         19 . The method of  claim 16 , wherein the producing the flow passageway includes electrochemically etching the base member such that the flow passageway includes a plurality of flow structures. 
     
     
         20 . The method of  claim 16 , wherein the flow passageway is an inlet flow passageway, the method further comprising:
 producing an outlet flow passageway in a third portion of the base member, the outlet flow passageway defining a fourth direction of flow, the fourth direction of flow the same as the first direction of flow.