Heat exchanger with improved liquid/gas mixing device

Abstract

The invention concerns a heat exchanger comprising several plates arranged parallel to one another and to a longitudinal direction so as to define a first series of passages for channeling at least one first fluid and a second series of passages for channeling at least one second fluid which is to be brought into a heat-exchange relationship with at least said first fluid, a mixer device being arranged in said at least one passage of the first series and comprising at least one first channel for the flow of a first phase of the fluid in the longitudinal direction, at least one second channel for the flow of a second phase of the fluid, and a plurality of orifices fluidically connecting the first channel to the second channel, said orifices occupying successive positions in the longitudinal direction. According to the invention, the distances between two successive positions, measured parallel to the longitudinal direction, are variable.

1 - 16 . (canceled) 
     
     
         17 . A heat exchanger comprising several plates arranged parallel to one another and to a longitudinal direction so as to define a plurality of passages for channeling at least a first fluid which is to be brought into a heat-exchange relationship with at least a second fluid, a mixer device being arranged in at least one passage and comprising:
 at least one first channel for the flow of a first phase of the first fluid parallel to the longitudinal direction;   at least one second channel for the flow of a second phase of the first fluid; and   a plurality of orifices fluidically connecting the first channel to the second channel, said orifices occupying successive positions in the longitudinal direction, wherein the distances between the successive positions, measured parallel to the longitudinal direction, are variable.   
     
     
         18 . The exchanger as claimed in  claim 17 , wherein the distances between the successive positions vary monotonically or near-monotonically in the longitudinal direction. 
     
     
         19 . The exchanger as claimed in  claim 17 , wherein the exchanger exhibits, in the longitudinal direction, an increase in the distances between two successive positions. 
     
     
         20 . The exchanger as claimed in  claim 17 , wherein the exchanger exhibits, in the longitudinal direction, a decrease in the distances between two successive positions. 
     
     
         21 . The exchanger as claimed in  claim 17 , wherein the exchanger is divided, in the longitudinal direction, into at least a first portion and a second portion, the first portion exhibiting, in the longitudinal direction, an increase in the distances between two successive positions, and the second portion exhibiting, in the longitudinal direction, a decrease in the distances between two successive positions. 
     
     
         22 . The exchanger as claimed in  claim 17 , wherein the mixer device is configured for a separate introduction of the first phase and of the second phase into the at least one first channel and into the at least one second channel, respectively, the first channel comprising a first inlet designed to supply said first channel with the first phase of the first fluid and a second inlet, separate from the first inlet, designed to supply said at least one second channel with the second phase of the first fluid. 
     
     
         23 . The exchanger as claimed in  claim 17 , wherein the first channel and the second channel are rectilinear in shape. 
     
     
         24 . The exchanger as claimed in  claim 17 , wherein the the mixer device comprises several first channels and several second channels, each first channel comprising at least one orifice fluidically connecting said first channel to a given second channel. 
     
     
         25 . The exchanger as claimed in  claim 17 , wherein the mixer device comprises several first channels succeeding one another in a lateral direction orthogonal to the longitudinal direction. 
     
     
         26 . The exchanger as claimed in  claim 17 , wherein the second channel extends in a lateral direction orthogonal to the longitudinal direction. 
     
     
         27 . A method for distributing a two-phase liquid/gas mixture in an exchanger as claimed in  claim 17 , said method comprising the following steps:
 i) arranging a mixer device in at least one passage of the exchanger;   ii) supplying said first channel of the mixer device with the first phase of the first fluid;   iii) supplying said second channel of the mixer device with the second phase of the first fluid, which is distinct from the first phase;   iv) establishing fluidic communication between the first channel and the second channel via the orifices so that a mixing between the first phase and the second phase takes place within the mixer device; and   v) distributing a mixture of the first phase and of the second phase at the outlet of the mixer device.   
     
     
         28 . A method for adjusting the position of the orifices of a mixer device incorporated into an exchanger as claimed in  claim 17 , said method comprising the following steps:
 a) positioning the orifices in such a way that their successive positions are separated by predetermined distances;   b) supplying the first channel with the first phase of the fluid such that the first phase of the first fluid flows in the longitudinal direction;   c) determining the mass flow rates of the first phase flowing through each orifice; and   d) for each orifice, repositioning the next orifice so that it is separated from the orifice by a modified distance equal to the mean of the predetermined distances multiplied by a correction factor, said correction factor being determined on the basis of the mass flow rate flowing through the orifice.   
     
     
         29 . The method as claimed in  claim 28 , wherein the correction factor is a function of the ratio between the mass flow rate flowing through the orifice and the mass flow rate averaged over all the orifices. 
     
     
         30 . The method as claimed in  claim 29 , said function is a polynomial function of the ratio, preferably an affine function of the ratio. 
     
     
         31 . The method as claimed in  claim 28 , further comprising a step e) of defining the distances modified in step d) as predetermined distances, steps c) to d) being reiterated at least once. 
     
     
         32 . The method as claimed in  claim 31  wherein steps c) to d) are repeated between 1 and 5 times. 
     
     
         33 . The method as claimed in  claim 31  wherein steps c) to d) are repeated at most twice. 
     
     
         34 . The method as claimed in  claim 28 , wherein the mixer device comprises several first channels, the method comprising, prior to step a), at least one step of selecting a subset of orifices which are arranged in one and the same first channel, steps a) to e) being applied to said sub set.