Heat exchanger and method of operating the same

Abstract

An evaporative heat exchanger includes first and second stacked plates forming a first fluid flow path between a first end and a second end. The first stacked plate defines a plane. Third and fourth stacked plates define a second fluid flow path. A fluid flow plate is positioned between the first and second stacked plates, and has a plurality of flow channels extending substantially parallel to the plane between the first end and the second end. At least one of the first and second stacked plates defines slots that form a portion of the first fluid flow path so that fluid flowing along the first fluid flow path flows along the flow channels in the first direction, then flows along at least one of the slots, then flows into adjacent flow channels and then along the adjacent flow channels in a second direction parallel to the first direction.

What is claimed is: 
     
         1 . An evaporative heat exchanger operable to at least partially vaporize fluid, the heat exchanger comprising:
 first and second stacked plates defining a first fluid flow path between the first and second stacked plates, the first and second stacked plates each having a first end and a second end, and the first stacked plate defines a plane;   third and fourth stacked plates defining a second fluid flow path between the third and fourth stacked plates, wherein the third stacked plate is positioned adjacent the second stacked plate; and   a fluid flow plate positioned between the first and second stacked plates, the fluid flow plate having a plurality of flow channels extending in a first direction between the first end and the second end, wherein the first direction is substantially parallel to the plane;   wherein at least one of the first and second stacked plates and the fluid flow plate defines a plurality of slots, wherein the plurality of slots form a portion of the first fluid flow path such that fluid flowing along the first fluid flow path flows along at least one of the flow channels in the first direction and then flows in a second direction into at least one of the plurality of slots, wherein the second direction is non-parallel to the plane, and then flows in a third direction toward an adjacent one of the flow channels, wherein the third direction is substantially parallel to the plane, and then in a fourth direction into the adjacent one of the flow channels, wherein the fourth direction is substantially non-parallel to the plane, and then in a fifth direction along the adjacent one of the flow channels, wherein the fifth direction is substantially parallel to the plane.   
     
     
         2 . The heat exchanger of  claim 1 , wherein at least one of the slots is an elongate slot extending along the third direction. 
     
     
         3 . The heat exchanger of  claim 1 , wherein the second direction is substantially perpendicular to the plane. 
     
     
         4 . The heat exchanger of  claim 1 , wherein the first direction is substantially perpendicular to the third direction. 
     
     
         5 . The heat exchanger of  claim 1 , wherein the first direction is substantially parallel to the fifth direction. 
     
     
         6 . The heat exchanger of  claim 1 , wherein at least one of the plurality of slots is formed in the first plate. 
     
     
         7 . The heat exchanger of  claim 1 , wherein at least one of the plurality of slots is formed in the second plate. 
     
     
         8 . The heat exchanger of  claim 1 , wherein the plurality of slots include at least one slot formed in the first plate and at least one slot formed in the second plate. 
     
     
         9 . The heat exchanger of  claim 1 , wherein the plurality of slots includes a first group of slots and a second group of slots, wherein the first group of slots is formed in the first plate and wherein the second group of slots is formed in the second plate. 
     
     
         10 . The heat exchanger of  claim 1 , wherein the fluid flow plate has convolutions that form adjacent the peaks and valleys, and wherein the plurality of flow channels are defined by peaks and valleys. 
     
     
         11 . The heat exchanger of  claim 1 , wherein the plurality of slots include at least one group of elongate slots each extending in the third direction, substantially perpendicular to the first direction. 
     
     
         12 . The heat exchanger of  claim 1 , further comprising a convoluted fin positioned between the third and fourth plates. 
     
     
         13 . An evaporative heat exchanger operable to at least partially vaporize fluid, the heat exchanger comprising:
 first and second stacked plates defining a first fluid flow path between the first and second stacked plates, the first and second stacked plates each having a first end and a second end, and the first stacked plate defines a plane;   third and fourth stacked plates defining a second fluid flow path between the third and fourth stacked plates, wherein the third stacked plate is positioned adjacent the second stacked plate; and   a fluid flow plate positioned between the first and second stacked plates, the fluid flow plate having a plurality of flow channels extending in a first direction between the first end and the second end, wherein the first direction is substantially parallel to the plane;   wherein at least one of the first and second stacked plates defines a plurality of slots, wherein the plurality of slots form a portion of the first fluid flow path such that fluid flowing along the first fluid flow path flows along at least one of the flow channels in the first direction, then flows along at least one of the plurality of slots, then flows into an adjacent one of the flow channels and then along the adjacent flow channel in a second direction, substantially parallel to the first direction.   
     
     
         14 . The heat exchanger of  claim 13 , wherein the plurality of slots are elongate and extend in a third direction, wherein the third direction is non-parallel to the plane. 
     
     
         15 . The heat exchanger of  claim 14 , wherein the third direction is substantially perpendicular to the first direction. 
     
     
         16 . The heat exchanger of  claim 13 , wherein at least one of the plurality of slots is an elongate slot. 
     
     
         17 . The heat exchanger of  claim 13 , wherein the plurality of slots includes a first plurality of slots formed in the first plate and a second plurality of slots formed in the second plate. 
     
     
         18 . The heat exchanger of  claim 17 , wherein each the first plurality of slots are substantially aligned with a corresponding one of the second plurality of slots in a direction substantially perpendicular to the plane. 
     
     
         19 . The heat exchanger of  claim 13 , wherein the fluid flow plate has convolutions that form adjacent peaks and valleys, and wherein the plurality of flow channels are defined by the peaks and valleys. 
     
     
         20 . The heat exchanger of  claim 13 , further comprising a convoluted fin positioned between the third and fourth plates.