Climate control systems for motor vehicles and methods of operating the same

Abstract

Climate control systems and methods of operating climate control systems for motor vehicles are provided herein. In one example, the method comprises the steps of expanding a condensed refrigerant stream with an expansion valve to form a partially expanded refrigerant stream. The partially expanded refrigerant stream comprises a refrigerant liquid phase and a refrigerant vapor phase. The partially expanded refrigerant stream is separated with a liquid-vapor separator into a refrigerant liquid stream and a refrigerant vapor stream. Heat is exchanged between air passing across or through an evaporator and the refrigerant liquid stream passing internally through and expanding in the evaporator to form a superheated refrigerant gas stream.

What is claimed is: 
     
         1 . A climate control system for a motor vehicle, the system comprising:
 a refrigeration loop circuit configured to advance a refrigerant;   a compressor disposed along the refrigeration loop circuit and configured to compress the refrigerant to form a high-pressure refrigerant gas stream;   a condenser disposed along the refrigeration loop circuit downstream from the compressor and configured to condense the high-pressure refrigerant gas stream to form a condensed refrigerant stream;   an expansion valve disposed along the refrigeration loop circuit downstream from the condenser and configured to expand the condensed refrigerant stream to form a partially expanded refrigerant stream that comprises a refrigerant liquid phase and a refrigerant vapor phase;   a liquid-vapor separator disposed along the refrigeration loop circuit in fluid communication with the expansion valve and configured to separate the partially expanded refrigerant stream into a refrigerant liquid stream and a refrigerant vapor stream, wherein the liquid-vapor separator contains a desiccant for removing water from at least a portion of the partially expanded refrigerant stream to form the refrigerant liquid stream that is substantially depleted of water; and   an evaporator disposed along the refrigeration loop circuit downstream from the liquid-vapor separator and configured to exchange heat between air passing across or through the evaporator and the refrigerant liquid stream passing internally through and expanding in the evaporator to form a superheated refrigerant gas stream.   
     
     
         2 . The system of  claim 1 , wherein the refrigeration loop circuit is configured to combined the refrigerant vapor stream with the superheated refrigerant gas stream downstream from the evaporator. 
     
     
         3 . The system of  claim 2 , wherein the refrigeration loop circuit comprises a bypass section that fluidly communicates the refrigerant vapor stream from the liquid-vapor separator to the superheated refrigerant gas stream upstream from the compressor. 
     
     
         4 . The system of  claim 3 , wherein the expansion valve is configured such that the superheated refrigerant gas stream passes through the expansion valve to regulate flow of the partially expanded refrigerant stream to the liquid-vapor separator, and wherein the bypass section fluidly communicates the refrigerant vapor stream to the superheated refrigerant gas stream downstream from the expansion valve. 
     
     
         5 . The system of  claim 1 , wherein the expansion valve is coupled directly to the liquid-vapor separator such that the liquid-vapor separator receives the partially expanded refrigerant stream directly from the expansion valve and the expansion valve receives the refrigerant vapor stream directly from the liquid-vapor separator before the refrigerant vapor stream is introduced to the superheated refrigerant gas stream. 
     
     
         6 . The system of  claim 1 , wherein the expansion valve is configured as an electronic expansion valve that senses conditions of the superheated refrigerant gas stream and is responsive to the conditions to regulate flow of the partially expanded refrigerant stream to the liquid-vapor separator. 
     
     
         7 . The system of  claim 1 , further comprising an internal heat exchanger disposed along the refrigeration loop circuit and having a first fluid conduit and a second fluid conduit, the first fluid conduit is downstream from the condenser and upstream from the expansion valve and the second fluid conduit is downstream from the evaporator and upstream from the compressor, and wherein the internal heat exchanger is configured for indirect heat exchange between the condensed refrigerant stream and the superheated refrigerant gas stream. 
     
     
         8 . The system of  claim 7 , wherein the refrigeration loop circuit is configured to fluidly communicates the refrigerant vapor stream to the superheated refrigerant gas stream upstream from the internal heat exchanger. 
     
     
         9 . The system of  claim 1 , wherein the climate control system does not comprise an integrated receiver for receiving the condensed refrigerant stream from the condenser. 
     
     
         10 . The system of  claim 1 , wherein the liquid-vapor separator has storage capacity for storing a column of the refrigerant liquid stream. 
     
     
         11 . The system of  claim 1 , wherein the liquid-vapor separator is configured as a cyclonic-type separator. 
     
     
         12 . The system of  claim 1 , wherein the liquid-vapor separator is configured as a baffle-type separator. 
     
     
         13 . The system of  claim 1 , wherein the liquid-vapor separator is configured as a coalescence-type separator. 
     
     
         14 . A climate control system for a motor vehicle, the system comprising:
 a refrigeration loop circuit configured to advance a refrigerant;   a compressor disposed along the refrigeration loop circuit and configured to compress the refrigerant to form a high-pressure refrigerant gas stream;   a condenser disposed along the refrigeration loop circuit downstream from the compressor and configured to condense the high-pressure refrigerant gas stream to form a condensed refrigerant stream;   an expansion valve disposed along the refrigeration loop circuit downstream from the condenser and configured to expand the condensed refrigerant stream to form a partially expanded refrigerant stream that comprises a refrigerant liquid phase and a refrigerant vapor phase;   a liquid-vapor separator disposed along the refrigeration loop circuit in fluid communication with the expansion valve and configured to separate the partially expanded refrigerant stream into a refrigerant liquid stream and a refrigerant vapor stream, wherein the expansion valve is coupled directly to the liquid-vapor separator such that the liquid-vapor separator receives the partially expanded refrigerant stream directly from the expansion valve and the expansion valve receives the refrigerant vapor stream directly from the liquid-vapor separator; and   an evaporator disposed along the refrigeration loop circuit downstream from the liquid-vapor separator and configured to exchange heat between air passing across or through the evaporator and the refrigerant liquid stream passing internally through and expanding in the evaporator to form a superheated refrigerant gas stream.   
     
     
         15 . A method of operating a climate control system for a motor vehicle, the method comprising the steps of:
 expanding a condensed refrigerant stream with an expansion valve to form a partially expanded refrigerant stream that comprises a refrigerant liquid phase and a refrigerant vapor phase;   separating the partially expanded refrigerant stream with a liquid-vapor separator into a refrigerant liquid stream and a refrigerant vapor stream, and wherein separating includes removing water from at least a portion of the partially expanded refrigerant stream with a desiccant contained in the liquid-vapor separator to form the refrigerant liquid stream that is substantially depleted of water; and   exchanging heat between air passing across or through an evaporator and the refrigerant liquid stream passing internally through and expanding in the evaporator to form a superheated refrigerant gas stream.   
     
     
         16 . The method of  claim 15 , further comprising the step of:
 combining the refrigerant vapor stream with the superheated refrigerant gas stream.   
     
     
         17 . The method of  claim 16 , further comprising the step of:
 directing the superheated refrigerant gas stream through the expansion valve to regulate flow of the partially expanded refrigerant stream to the liquid-vapor separator, and wherein the step of combining includes combining the refrigerant vapor stream with the superheated refrigerant gas stream downstream from the expansion valve.   
     
     
         18 . The method of  claim 16 , further comprising the step of:
 directing the refrigerant vapor stream through the expansion valve prior to the step of combining.   
     
     
         19 . The method of  claim 18 , wherein the step of directing includes introducing the refrigerant vapor stream directly into the expansion valve from the liquid-vapor separator. 
     
     
         20 . The method of  claim 15 , further comprising the step of:
 storing a column of the refrigerant liquid stream in the liquid-vapor separator.