Liquid-Vapor Separator For A Minichannel Heat Exchanger

Abstract

A method and apparatus for promoting uniform refrigerant flow in a minichannel heat exchanger by providing a liquid-vapor separator between an expansion device and the inlet header such that the refrigerant vapor will pass directly to the compressor and only the liquid refrigerant will pass to the inlet header. The liquid-vapor separation is accomplished by way of a float valve which prevents the flow of liquid refrigerant to the compressor and the flow of refrigerant vapor from the outlet manifold, through the valve and back to the inlet manifold. A second float valve may be provided between a downstream end of the inlet manifold and the compressor for the purpose of removing any residual vapor from the liquid.

1 . A liquid-vapor separator for a heat exchanger of the type having inlet and outlet manifolds fluidly interconnected by a plurality of parallel minichannels for conducting the flow of refrigerant therebetween, comprising:
 an inlet chamber fluidly connected between said inlet manifold and an expansion device that is adapted to deliver two phase refrigerant thereto;   a bypass duct fluidly interconnected between said inlet chamber and a compressor inlet; and   a float valve disposed within said bypass duct and operable to permit the flow of refrigerant vapor to said compressor but not to permit the flow of liquid refrigerant thereto.   
   
   
       2 . A liquid-vapor separator as set forth in  claim 1  wherein said inlet chamber is connected to the expansion device by an inlet line and further wherein said inlet line is connected to said inlet chamber at an upper portion thereof. 
   
   
       3 . A liquid-vapor separator as set forth in  claim 2  wherein said inlet chamber is so constructed as to permit the flow of liquid refrigerant to said inlet manifold but the presence of liquid refrigerant in said inlet chamber prevents the flow of refrigerant vapor to said inlet manifold. 
   
   
       4 . (canceled) 
   
   
       5 . A liquid-vapor separator as set forth in  claim 1  wherein said float valve includes an outlet port and float member moveable upwardly to seat against and seal said outlet port. 
   
   
       6 . A liquid-vapor separator as set forth in  claim 5  wherein said valve further includes an inlet port against which the float member can seat as it moves downwardly to prevent the flow of refrigerant vapor downwardly therethrough. 
   
   
       7 . A liquid-vapor separator as set forth in  claim 1  wherein said outlet manifold is fluidly connected to the compressor. 
   
   
       8 . A liquid-vapor separator as set forth in  claim 1  and including a conduit fluidly interconnecting a downstream end of said inlet manifold to said compressor and said float valve is disposed within said conduit for removal of any residual vapor from a liquid. 
   
   
       9 . A liquid-vapor separator as set forth in  claim 8  wherein said float valve and an outlet port and a float member that is upwardly moveable to seat thereagainst. 
   
   
       10 . A liquid-vapor separator as set forth in  claim 9  wherein said float valve includes an inlet port against which the float member can seat. 
   
   
       11 . A method of promoting uniform refrigerant flow from an inlet manifold of a heat exchanger to a plurality of parallel minichannels fluidly connected thereto, comprising the steps of:
 providing an inlet chamber for fluidly interconnecting the inlet manifold to an expansion device adapted to deliver two phase refrigerant thereto;   providing a bypass duct for fluidly interconnecting said inlet chamber and a compressor inlet; and   providing a float valve within said bypass duct so as to permit the flow of refrigerant vapor to said compressor but not permit the flow of liquid refrigerant thereto.   
   
   
       12 . A method as set forth in  claim 11  including the steps of connecting the expansion device to an upper portion of said inlet chamber by way of an inlet line. 
   
   
       13 . (canceled) 
   
   
       14 . A method as set forth in  claim 11  wherein said float valve includes an outlet port and float member moveable upwardly to seat against and seal said outlet port. 
   
   
       15 . A method as set forth in  claim 14  wherein said float valve further includes an inlet port against which the float member can seat as it moves downwardly to prevent the flow of refrigerant vapor downwardly therethrough. 
   
   
       16 . A method as set forth in  claim 15  and including the further step of fluidly connecting said outlet manifold to the compressor. 
   
   
       17 . A method as set forth in  claim 11  and including the further step of fluidly interconnecting a downstream end of said inlet manifold to said compressor by way of a conduit. 
   
   
       18 . A method as set forth in  claim 17  and including the further step of providing said float valve within said conduit for removal of any residual vapor from a liquid. 
   
   
       19 . A method as set forth in  claim 18  wherein said float valve includes an outlet port and a float member that is upwardly moveable to seat thereagainst. 
   
   
       20 . A method as set forth in  claim 19  wherein said float valve includes an inlet port against which the float member can seat.