Microchannel heat exchanger with enhanced refrigerant distribution

Abstract

An evaporator includes a manifold receiving a distributor insert. The distributor insert receives the flow of refrigerant to be delivered into the manifold, and has openings to communicate this refrigerant into a plurality of chambers which are defined between adjacent dividing elements of the distributor insert within the manifold. In this manner, these chambers are each associated with distinct heat transfer tubes and such that these chambers are isolated from each other.

1 . A heat exchanger comprising:
 a plurality of heat transfer tubes;   a manifold for communicating refrigerant into said plurality of heat transfer tubes, and a distributor insert connected to a source of refrigerant and having a plurality of orifices in an outer periphery of said distributor insert and dividing elements on an outer wall of said distributor insert such that a plurality of distribution chambers are defined and associated with said plurality of heat transfer tubes.   
     
     
         2 . The heat exchanger as set forth in  claim 1 , wherein the heat exchanger is an evaporator, and said manifold is an inlet manifold. 
     
     
         3 . The heat exchanger as set forth in  claim 1 , wherein said distributor insert and said dividing elements improve refrigerant distribution in said heat exchanger. 
     
     
         4 . The heat exchanger as set forth in  claim 1 , wherein said manifold is an intermediate manifold. 
     
     
         5 . The heat exchanger as set forth in  claim 1 , wherein said distributor insert extends along only a portion of said manifold, and is not aligned with heat transfer tubes communicating into said manifold, but is aligned with heat transfer tubes communicating out of said manifold. 
     
     
         6 . The heat exchanger as set forth in  claim 1 , wherein said dividing elements are spaced uniformly along a length of said distributor insert. 
     
     
         7 . The heat exchanger as set forth in  claim 1 , wherein said dividing elements are attached to said distributor insert by one of mechanical attachment and chemical bonding. 
     
     
         8 . The heat exchanger as set forth in  claim 1 , wherein said dividing elements are flat plates having a cutout portion at an outer periphery to provide clearance for said heat transfer tubes. 
     
     
         9 . The heat exchanger as set forth in  claim 1 , wherein the distributor insert has a round cross-sectional shape. 
     
     
         10 . The heat exchanger as set forth in  claim 1 , wherein said manifold has an internal bore of a round cross-sectional shape. 
     
     
         11 . The heat exchanger as set forth in  claim 1 , wherein the refrigerant passing through said distributor insert is a two-phase refrigerant. 
     
     
         12 . The heat exchanger as set forth in  claim 1 , wherein the heat exchanger is a microchannel heat exchanger. 
     
     
         13 . A refrigerant system comprising:
 a compressor, said compressor for compressing a refrigerant and delivering it downstream into a condenser, refrigerant from said condenser passing through an expansion device and then into an evaporator;   at least one of said condenser and evaporator including a plurality of heat transfer tubes for receiving a refrigerant, and passing the refrigerant along a path from an inlet end to an outlet end, and a manifold for communicating with an inlet end of said heat transfer tubes, said manifold receiving a distributor insert, connected to a source of refrigerant and having a plurality of orifices at an outer periphery and a plurality of dividing elements between an outer wall of said distributor insert and an inner wall of said manifold to define a plurality of separation chambers within said manifold, with at least some of said heat transfer tubes being associated with different ones of said separation chambers and isolated from others of said separation chambers by said dividing elements.   
     
     
         14 . The refrigerant system as set forth in  claim 13 , wherein said distributor insert extends from an upstream end of said manifold toward a downstream end of said manifold, and the size of said separation chambers defined between adjacent ones of said dividing elements is determined to optimize the flow of refrigerant within the plurality of heat transfer tubes. 
     
     
         15 . The refrigerant system as set forth in  claim 13 , wherein said plurality of heat transfer tubes, each including a plurality of channels, spaced generally perpendicularly to an upstream to downstream direction of said distributor insert. 
     
     
         16 . The refrigerant system as set forth in  claim 13 , wherein the heat exchanger is an evaporator, and said manifold is an inlet manifold. 
     
     
         17 . The refrigerant system as set forth in  claim 13 , wherein said manifold is an intermediate manifold. 
     
     
         18 . The refrigerant system as set forth in  claim 17 , wherein said distributor insert extends along only a portion of said manifold, and is not aligned with heat transfer tubes communicating into said manifold, but is aligned with heat transfer tubes communicating out of said manifold 
     
     
         19 . The refrigerant system as set forth in  claim 13 , wherein the heat exchanger is a microchannel heat exchanger. 
     
     
         20 . The refrigerant system as set forth in  claim 13 , wherein said dividing elements are flat plates having a cutout portion at an outer periphery to provide clearance for said heat transfer tubes.