System for refrigeration, heating or air-conditioning technology, particularly refrigeration systems

Abstract

The present disclosure relates to a system for refrigeration, heating or air-conditioning technology, particularly a refrigeration system, including a working medium circuit, which has a compressor, a condenser, an expansion valve, and an evaporator connected successively in the flow direction. Particularly stable operating behavior of the system is achieved in a simple manner in that means, which thermally couple the liquid operating medium flowing to the expansion valve to the operating medium flowing from the expansion valve to the evaporator, are provided in order to maintain the temperature of the liquid operating medium constant.

1 . A system for refrigeration, heating or air-conditioning technology, particularly a refrigeration system ( 40 ,  40 ′), with a working medium circuit which comprises a compressor ( 12 ), a condenser ( 11 ), an expansion valve ( 15 ) and an evaporator ( 14 ) one behind the other in the direction of flow, characterized in that, to keep the temperature of the liquid working medium constant upstream of the expansion valve ( 15 ), means ( 25 ) are provided which couple the liquid working medium flowing to the expansion valve ( 15 ) thermally to the working medium flowing from the expansion valve ( 15 ) to the evaporator ( 14 ). 
     
     
         2 . The system as claimed in  claim 1 , characterized in that the means for keeping the temperature of the liquid working medium constant upstream of the expansion valve ( 15 ) comprise a stabilizer ( 25 ) in the form of a heat exchanger, through which the working medium flowing from the expansion valve ( 15 ) to the evaporator ( 14 ) flows on one side and through which the liquid working medium flowing to the expansion valve ( 15 ) flows on the other side. 
     
     
         3 . The system as claimed in  claim 2 , characterized in that the working medium flows through the stabilizer ( 25 ) in cocurrent or countercurrent. 
     
     
         4 . The system as claimed in  claim 2  or  3 , characterized in that the evaporator ( 14 ) is followed by an internal heat exchanger ( 26 ), in which, on one side, the working medium coming from the evaporator ( 14 ) is re-evaporated and/or superheated and, on the other side, the working medium coming from the condenser ( 11 ) is supercooled before entry into the stabilizer ( 25 ). 
     
     
         5 . The system as claimed in  claim 4 , characterized in that the internal heat exchanger ( 26 ) is designed as a thermally long heat exchanger. 
     
     
         6 . The system as claimed in  claim 4 , characterized in that an external supercooler ( 28 ) is inserted between the condenser ( 11 ) and the internal heat exchanger ( 26 ). 
     
     
         7 . The system as claimed in  claim 4  or  5 , characterized in that a waste heat utilization exchanger ( 27 ) is arranged between the compressor ( 12 ) and the condenser ( 11 ). 
     
     
         8 . A method for operating a system as claimed in one of  claims 4  to  7 , characterized in that the internal heat exchanger ( 26 ) is selectively operated solely as a superheater for the working medium flowing to the compressor ( 12 ) or as a further evaporator stage. 
     
     
         9 . The method as claimed in  claim 8 , characterized in that the internal heat exchanger ( 26 ) is operated selectively, as a function of the inlet temperature of the liquid working medium into the internal heat exchanger ( 26 ), solely as a superheater for the working medium flowing to the compressor ( 12 ) or as a further evaporator stage. 
     
     
         10 . The method as claimed in  claim 8  or  9 , characterized in that, in the system ( 40 ,  40 ′), the highest possible power in the evaporator ( 14 ) is transmitted to a secondary medium by means of the lowest possible mass flow on the cold side.