Multichannel tubes with deformable webs

Abstract

The present disclosure is directed to multichannel tubes that can be expanded to assemble the multichannel tubes within plate fin heat exchangers. The multichannel tubes each include several generally parallel flow paths, which are separated from one another by deformable webs slanted in a common direction across a width of the multichannel tubes. The webs may deform upon expansion of the tubes with a high pressure fluid. During expansion, the webs may stretch, shift positions, and/or change shape to allow the outer dimensions of the tube to increase. The multichannel tubes may be designed to expand to fill openings of plate fins, creating an interference fit between the multichannel tubes and the plate fins.

1 . A heat exchanger tube, comprising:
 a top wall;   a bottom wall disposed generally opposite from the top wall and separated by a height of the heat exchanger tube;   a pair of sidewalls extending between the top and bottom walls and separated by a width of the heat exchanger tube, wherein at least one of the pair of sidewalls has a chamfered edge configured to deform in response to hydraulic expansion of the heat exchanger tube to produce a curved and generally symmetrical sidewall; and   a plurality of deformable webs spaced across the width and extending between the top wall and the bottom wall to form a plurality of generally parallel flow paths therebetween, wherein the deformable webs are configured to deform in response to the hydraulic expansion of the heat exchanger tube to increase the height of the heat exchanger tube.   
     
     
         2 . The heat exchanger tube of  claim 1 , wherein the deformable webs are linear and are disposed generally parallel to one another. 
     
     
         3 . The heat exchanger tube of  claim 1 , wherein the deformable webs comprise a relatively constant cross-sectional shape along a length of the heat exchanger tube. 
     
     
         4 . The heat exchanger tube of  claim 1 , wherein the chamfered edge comprises an angled section that connects the top wall or the bottom wall to a curved profile of the sidewall. 
     
     
         5 . The heat exchanger tube of  claim 1 , wherein the deformable webs are slanted in a common direction towards one of the pair of sidewalls at an angle less than approximately 45 degrees with respect to the bottom wall. 
     
     
         6 . The heat exchanger tube of  claim 1 , wherein the flow paths each comprise a generally parallelogram shape. 
     
     
         7 . The heat exchanger tube of  claim 1 , wherein the flow paths each comprise a pair of rounded corners disposed opposite of one another and a pair of angled corners disposed opposite of one another. 
     
     
         8 . The heat exchanger tube of  claim 1 , wherein the deformable webs are slanted at an acute angle with respect to the bottom wall and are configured to become less slanted in response to the hydraulic expansion to increase the acute angle. 
     
     
         9 . A heat exchanger tube, comprising:
 a top wall;   a bottom wall disposed generally opposite from the top wall and separated by a height of the heat exchanger tube;   a pair of sidewalls extending between the top and bottom walls and separated by a width of the heat exchanger tube, wherein each of the sidewalls has a chamfered edge; and   a plurality of deformable webs spaced across the width, slanted in a common direction across the width with respect to the bottom wall and the top wall, and extending between the top wall and the bottom wall to form a plurality of generally parallel flow paths therebetween, wherein the deformable webs are configured to deform in response to the hydraulic expansion of the heat exchanger tube to increase the height of the heat exchanger tube.   
     
     
         10 . The heat exchanger tube of  claim 9 , wherein the pair of sidewalls comprise curved profiles connecting the top and bottom walls, and wherein the chamfered edges each comprise an angled section connecting the top wall or the bottom wall to one of the curved profiles. 
     
     
         11 . The heat exchanger tube of  claim 9 , wherein the chamfered edges extend along a length of the heat exchanger tube from a first end to an opposite end. 
     
     
         12 . The heat exchanger tube of  claim 11 , wherein a first sidewall of the pair of sidewalls comprises a first chamfered edge extending from the top wall and wherein a second sidewall of the pair of sidewalls comprises a second chamfered edge extending from the bottom wall. 
     
     
         13 . The heat exchanger tube of  claim 9 , wherein at least one of the pair of sidewalls has a first chamfered edge extending from the top wall and a second chamfered edge extending from the bottom wall. 
     
     
         14 . The heat exchanger tube of  claim 9 , wherein the chamfered edges are configured to deform in response to hydraulic expansion to produce curved and generally symmetrical sidewalls. 
     
     
         15 . A method for assembling a heat exchanger, the method comprising:
 inserting a multichannel tube through a plurality of openings each disposed on a sheet of thermally conductive material; and   hydraulically expanding the multichannel tube to deform internal webs defining a plurality of generally parallel flow paths within the multichannel tube, to expand the multichannel tube into the plurality of openings, and to deform chamfered edges of the multichannel tube to produce curved and generally symmetrical sidewalls.   
     
     
         16 . The method of  claim 15 , wherein the openings encircle a cross-section of the multichannel tube. 
     
     
         17 . The method of  claim 15 , wherein the internal webs are slanted in a common direction across a width of the multichannel tube, and wherein hydraulically expanding comprises directing a fluid through the multichannel tube and pressurizing the fluid within the multichannel tube to reduce an amount of slant in the internal webs. 
     
     
         18 . The method of  claim 15 , wherein hydraulically expanding comprises directing refrigerant oil through the multichannel tube and pressurizing the refrigerant oil within the multichannel tube to shift a top portion of each internal web towards a first sidewall of the multichannel tube and to shift a bottom portion of each internal web towards an opposite sidewall of the multichannel tube. 
     
     
         19 . The method of  claim 15 , wherein the internal webs extend between a top wall and a bottom wall of the multichannel tube, and wherein hydraulically expanding comprises moving the top wall and the bottom wall laterally with respect to one another. 
     
     
         20 . The method of  claim 15 , wherein hydraulically expanding comprises pressurizing a fluid within the multichannel tube to a pressure that is between an operating pressure of the multichannel tube and a burst pressure of the multichannel tube.