Tube for use in fluid evaporation techniques, in particular food fluid

Abstract

The invention concerns a welded stainless steel tube for use in fluid evaporation techniques, particularly a food fluid, characterized in that it comprises, on its outer heat-exchanging surface, mostly smooth, localized means for accumulating and conducting condensations generated on the heat-exchanging smooth surface, means consisting of elevations in the form of shoulders extending over the length of the tube and capable of forming recesses distributed over said tube length.

1 . A method for improving heat exchanges in a heat exchanger for the evaporation of a fluid, particularly in the food industry, the exchanger having exchange tubes intended for heat exchange and having smooth uniform external surfaces, wherein: 
 there are produced, on at least one of the smooth surfaces of the exchange tubes, localised condensation accumulation and drainage means, means intended to attract, by capillary attraction, condensed liquid film, which is deposited uniformly on said at least one, mostly smooth, surface of the tube, and    said condensed liquid film being drained by means of the localised condensation accumulation and drainage means.    
     
     
         2 . A method according to  claim 1 , wherein there is produced, on at least one of the smooth surfaces of the exchange tubes, at least one elevation in the form of a shoulder extending over the length of said tube and whose height is less than 0.5 mm and preferably less than 0.2 mm, an elevation defining a longitudinal impression with an edge that attracts, by capillary attraction, condensed liquid film, which is deposited uniformly over said at least one, mostly smooth, surface of the tube.