Spacer element with surface texturing, and associated heat exchanger and production method

Abstract

Certain embodiments of the invention relate to a spacer element for a heat exchanger of the brazed plate and fin type, intended to be fitted between a first plate and a second plate of the exchanger, said spacer element comprising at least a first assembly portion configured to be assembled with the first plate and comprising a first pair of opposite surfaces, one of the surfaces of the first pair being oriented toward the first plate and the other of the surfaces of the first pair being oriented toward the second plate when the spacer element is in the fitted state, several fins or corrugation legs extending from said first assembly portion so as to delimit, when the spacer element is in the fitted state, a plurality of channels for the flow of a first fluid, and at least one surface texturing in the form of a porous structure or of reliefs formed on the surface of the spacer element, at least one fin or corrugation leg exhibiting said surface texturing. According to the invention, the first assembly portion is free of surface texturing on the surface of the first pair which, in the fitted state, is oriented toward the first plate.

1 - 20 . (canceled) 
     
     
         21 . A spacer element for a heat exchanger of the brazed plate and fin type, intended to be fitted between a first plate and a second plate of the exchanger, said spacer element comprising:
 at least a first assembly portion configured to be assembled with the first plate and comprising a first pair of opposite surfaces, one of the surfaces of the first pair being oriented toward the first plate and the other of the surfaces of the first pair being oriented toward the second plate when the spacer element is in the fitted state,   several fins or corrugation legs extending from said first assembly portion so as to delimit, when the spacer element is in the fitted state, a plurality of channels for the flow of a first fluid, and   at least one surface texturing in the form of a porous structure or of reliefs formed on a surface of the spacer element, at least one fin or corrugation leg exhibiting said surface texturing,   wherein the first assembly portion is free of surface texturing on the surface of the first pair which, in the fitted state, is oriented toward the first plate.   
     
     
         22 . The element as claimed in  claim 21 , wherein the spacer element comprises a massive or solid substrate, the surface texturing being formed on a surface of the substrate. 
     
     
         23 . The element as claimed in  claim 21 , wherein at least one fin or corrugation leg comprises a third pair of opposite surfaces, one and/or the other of the surfaces of the third pair exhibiting said surface texturing. 
     
     
         24 . The element as claimed in  claim 23 , wherein all, or almost all, of one and the other of the surfaces of the third pair exhibits said surface texturing. 
     
     
         25 . The element as claimed in  claim 21 , wherein the first assembly portion exhibits the surface texturing on the surface of the first pair which, in the fitted state, is oriented toward the second plate. 
     
     
         26 . The element as claimed in  claim 21 , wherein the first assembly portion is arranged between two successive fins or corrugation legs, the surface of the first pair which, in the fitted state, is oriented toward the second plate having two ends each one connected to a respective surface of each of the two fins or corrugation legs, the surface of the first pair and said respective surfaces of the fins exhibiting the surface texturing. 
     
     
         27 . The element as claimed in  claim 21 , further comprising at least a second assembly portion configured to be assembled with the second plate and comprising a second pair of opposite surfaces, one of the surfaces of the second pair being oriented toward the first plate and the other of the surfaces of the second pair being oriented toward the second plate when the spacer element is in the fitted state, said second assembly portion being free of surface texturing on at least the surface of the second pair which, in the fitted state, is oriented toward the second plate. 
     
     
         28 . The element as claimed in  claim 27 , wherein the second assembly portion exhibits the surface texturing on the surface of the second pair which, in the fitted state, is oriented toward the first plate. 
     
     
         29 . The element as claimed in  claim 27 , wherein the second assembly portion is arranged between two successive fins or corrugation legs, the surface of the second pair which, in the fitted state, is oriented toward the first plate having two ends each one connected to a respective surface of each of the two fins or corrugation legs, said surface of the second pair and said respective surfaces of the fins exhibiting the surface texturing. 
     
     
         30 . The element as claimed in  claim 21 , wherein the first assembly portion and/or the second assembly portion are arranged, in the fitted state, parallel to the first and second plates, the fins or corrugation legs succeeding one another in a lateral direction and, in the fitted state, delimiting a plurality of channels which are configured to channel the first fluid in a longitudinal direction parallel to the first and second plates and orthogonal to the lateral direction. 
     
     
         31 . The element as claimed in  claim 30 , wherein that said at least one fin or corrugation leg extend in a plane parallel to the longitudinal direction and form an angle with respect to the first assembly portion and/or the second assembly portion, the angle being less than or equal to 90°. 
     
     
         32 . The element as claimed in  claim 21 , wherein the surface texturing is in the form of a porous structure having an open porosity of between 15 and 60%, or in the form of reliefs defining, in transverse cross section, cavities that are open to the surface of the spacer element. 
     
     
         33 . The element as claimed in  claim 21 , wherein the element is in the form of a corrugated product comprising a succession of corrugation legs alternately connected by corrugation crests and corrugation troughs, at least one corrugation crest comprising said first assembly portion and/or at least one corrugation trough comprising said second assembly portion. 
     
     
         34 . The element as claimed in  claim 33 , wherein the corrugation legs succeed one another in a lateral direction, the corrugated product having a density, defined as being the number of corrugation legs per unit length measured in the lateral direction, of less than 18 legs per 2.54 centimeters. 
     
     
         35 . The element as claimed in  claim 33 , wherein the corrugated product is formed from a flat product having a thickness of at least 0.15 mm. 
     
     
         36 . A heat exchanger of the brazed plate and fin type comprising a plurality of plates arranged parallel to each other so as to define a series of passages for the flow of a first fluid to be placed in a heat-exchange relationship with at least one second fluid, and at least one spacer element fitted between two successive plates that define a passage so as to form, within the passage, several channels for the flow of said first fluid, wherein the spacer element is as claimed in  claim 21 . 
     
     
         37 . A method for producing a spacer element for a heat exchanger of the brazed plate and fin type, said method comprising the following steps:
 a) shaping the spacer element so that it exhibits fins or corrugation legs which, when the spacer element is fitted between a first plate and a second plate of the exchanger, delimit a plurality of channels for the flow of a first fluid, and at least one first assembly portion configured to be assembled with a first plate and comprising a first pair of opposite surfaces of which one is oriented toward the first plate and the other is oriented toward the second plate when the spacer element is in the fitted state;   c) forming a surface texturing in the form of a porous structure or of reliefs over all, or almost all, of the spacer element; and   d) selectively removing at least a portion of said surface texturing extending over that one of the surfaces of the first pair which, in the fitted state, is oriented toward the first plate.   
     
     
         38 . The method as claimed in  claim 37 , further comprising, prior to step c), a step b) of depositing a meltable coating on that one of the surfaces of the first pair which, in the fitted state, is oriented toward the first plate, step d) comprising a heat treatment of the spacer element in such a way as to remove the meltable coating and the portion of surface texturing that is formed on said meltable coating. 
     
     
         39 . The method as claimed in  claim 38 , further comprising, prior to step c), the application of a mask to that one of the surfaces of the first pair which, in the fitted state, is oriented toward the first plate, step d) being performed by removing the mask. 
     
     
         40 . The method as claimed in  claim 39 , wherein step d) is performed mechanically.