Flooded evaporator

Abstract

A flooded evaporator is provided which can remove floating mist more exactly resulting in that the refrigerant mist is prevented from being sucked into the compressor, and with which heat transfer between the medium to be cooled and refrigerant liquid is improved. The evaporator is composed such that; a tubular housing ( 3 ) is provided to erect from a horizontal cylindrical container ( 1 ) which forms a heat exchanging section with a heat exchanger ( 2 ) accommodated therein, an inner tube ( 12 ) for upwardly guiding refrigerant vapor generated in the heat exchanging section is provided, the inner tube ( 2 ) is covered by a loose cover ( 13 ) so that refrigerant vapor containing refrigerant mist flowed up in the inner tube ( 12 ) impinges against the loose cover ( 13 ) to be deflected downward to flow out from the inner tube ( 12 ), a space ( 17 ) is secured in the tubular housing ( 3 ) to allow refrigerant mist to fall down utilizing gravitational attraction, a demister ( 16 ) is provided in the tubular housing ( 3 ) above the space ( 17 ), the clearance area between the inner tube ( 12 ) and loose cover ( 13 ) is smaller than the clearance area between the outer periphery of the loose cover ( 13 ) and inner periphery of the tubular housing ( 3 ), and circulation paths ( 20 ) of refrigerant liquid are formed in the container ( 1 ).

1 . A flooded evaporator having a container that forms a heat exchanging section in which a heat exchanger is accommodated, the heat exchanger comprising cooling tubes in which a medium to be cooled flows and heat exchange is performed between the medium to be cooled and refrigerant liquid filled in the heat exchanging section to vaporize the refrigerant, 
 wherein a tubular housing is formed to extend upward from the container, an inner tube communicating to the heat exchanger to guide refrigerant vapor generated in the heat exchanger upward is provided, a loose cover is attached on top of the inner tube with a clearance retained between the loose cover and the top of the inner tube, the loose cover having downward extending parts with a clearance retained between the downward extending parts of the loose cover and the inner tube so that refrigerant vapor flowed up and impinged against the loose cover is deflected downward, and a demister is provided in the tubular housing in its upper part so that a space for separating refrigerant mist in upward-flowing refrigerant vapor through allowing the mist to fall downward by gravitational attraction is secured between the loose cover and the demister, and    further wherein area of the clearance between the downward extending parts of the loose cover and the inner tube is smaller than area of a clearance between the downward extending parts of the loose cover and the inner surface of the tubular housing.    
   
   
       2 . A flooded evaporator according to  claim 1 , wherein the heat exchanger is covered with a cover plate such that an upper part of the cover plate where the inner tube is provided is opened to allow communication of the heat exchanger to the inner tube, lower part is open to the heat exchanging section of the container, and circulation paths are formed between both sides of the cover plate and the inner surface of the container so that refrigerant liquid circulates flowing down the circulation paths, entering the heat exchanger from the opening in the lower part of the cover plate, flowing up in the heat exchanger, and separated refrigerant mist fallen down to the heat exchanging section of the container again flows down the paths as liquid refrigerant.  
   
   
       3 . A flooded evaporator according to  claim 1 , wherein the heat exchanger is comprised of a number of heat transfer plates arranged parallel to each other at certain spacing and a number of tubes crossing the heat transfer plates, in which tubes flows the medium to be cooled.  
   
   
       4 . A flooded evaporator according to  claim 2 , wherein the container for accommodating the heat exchanger and the heat exchanger have a circular cross section respectively, and the heat exchanger is placed in the container offset a little downward.  
   
   
       5 . A flooded evaporator according to  claim 1 , wherein at least two of the tubular housing are provided to the container forming the heat exchanging section to erect parallel to each other in longitudinal direction of the container.