Heat exchanger

Abstract

A heat exchanger has tubes defining first fluid passages through which a first fluid flows therein, an inlet part and an outlet part. Each tube has a first main wall and a second main wall. At least one of the first main wall and the second main wall has a projection projecting outside of the tube along a peripheral end and a first recess and a second recess recessed from the projection. The tubes are stacked such that the first and second main walls are opposed to each other and spaces are provided between the adjacent tubes by the projections. The spaces define second fluid passages through which a second fluid flows. The inlet part is in communication with the second fluid passages through the first recesses and the outlet part is in communication with the second fluid passages through the second recesses.

1 . A heat exchanger for performing heat exchange between a first fluid and a second fluid, comprising:
 a plurality of tubes, each of the tubes defining a first fluid passage therein through which the first fluid flows and having a first main wall and a second main wall, wherein at least one of the first main wall and the second main wall has a projection along its peripheral end, a first recess and a second recess, the projection projects outside of the tube, the first and second recesses are recessed from an end of the projection at predetermined positions, wherein the tubes are stacked such that the first main walls and the second main walls are opposed to each other, second fluid passages through which the second fluid flows are defined by spaces provided between opposed first and second main walls of the adjacent tubes and surrounded by the projections, first openings communicating with the second fluid passages are defined by the first recesses, and second openings communicating with the second fluid passages are defined by the second recesses;   a second fluid inlet part disposed in communication with the first openings for introducing the second fluid into the second fluid passages; and   a second fluid outlet part disposed in communication with the second openings for discharging the second fluid from the second fluid passages.   
   
   
       2 . The heat exchanger according to  claim 1 , wherein
 the second fluid inlet part includes an inlet portion for introducing the second fluid and a distributing portion disposed downstream of the inlet portion with respect to a flow of the second fluid for distributing the second fluid flowing from the inlet portion into the second fluid passages, and   the second fluid outlet part includes a collecting portion for collecting the second fluid having passed through the second fluid passages therein and an outlet portion for discharging the second fluid from the collecting portion.   
   
   
       3 . The heat exchanger according to  claim 1 , wherein
 both of the first and second main walls have the projections, the first recess and the second recess, and   the tubes are stacked such that the projections of the adjacent two tubes are opposed to and in contact with each other, the first recesses of the adjacent two tubes are opposed to each other to define the first opening and the second recesses of the adjacent two tubes are opposed to each other to define the second opening.   
   
   
       4 . The heat exchanger according to  claim 1 , wherein each of the first and second recesses has a dimension equal to a dimension of the projection with respect to a direction perpendicular to the first and second main walls. 
   
   
       5 . The heat exchanger according to  claim 1 , wherein
 the first and second main walls have a substantially rectangular shape, and   the first and second recesses are located along longitudinal sides of the rectangular shape and on diagonal positions.   
   
   
       6 . The heat exchanger according to  claim 1 , wherein
 each of the tubes has a flow-adjusting portion on at least one of the first main wall and the second main wall at a position corresponding to an upstream location respect to a flow of the first fluid flowing in the first fluid passage, and   the flow-adjusting portion is configured such that the second fluid is spread throughout the second fluid passage.   
   
   
       7 . The heat exchanger according to  claim 1 , wherein
 each of the tubes is constructed of a first tube member and a second tube member, and   the first main wall and the second main wall are included in the first and second tube members, respectively.   
   
   
       8 . The heat exchanger according to  claim 1 , wherein each of the tubes has an inner fin in the first fluid passage. 
   
   
       9 . The heat exchanger according to  claim 2 , further comprising:
 a side wall member attached to longitudinal sides of the plurality of tubes, wherein   the side wall member has a bulge at a position corresponding to the first openings,   the bulge provides a clearance therein and encases the first openings,   the distributing portion is defined by the bulge, and   the inlet portion has a pipe shape and is in communication with the clearance provided by the bulge.   
   
   
       10 . The heat exchanger according to  claim 2 , further comprising:
 a side wall member attached to longitudinal sides of the plurality of tubes, wherein   the side wall member has a bulge at a position corresponding to the second openings,   the bulge provides a clearance therein and encases the second openings,   the collecting portion is defined by the bulge, and   the outlet portion has a pipe shape and is in communication with the clearance provided by the bulge.   
   
   
       11 . The heat exchanger according to  claim 9 , wherein
 the plurality of tubes includes an outermost tube stacked at an outermost side, the outermost tube provides an outermost tube wall,   the outermost tube wall has an end projection along its peripheral end, a first end recess and a second end recess recessed from an end of the end projection, the heat exchanger further comprising:   an outer wall member disposed along the outermost tube wall such that an end passage is defined by a space provided between the outer wall member and the outermost tube wall and surrounded by the end projection, wherein   the end passage is in communication with the second fluid inlet part and the second fluid outlet part through the first end recess and the second end recess, respectively.   
   
   
       12 . The heat exchanger according to  claim 11 , further comprising:
 a tank having a connecting wall and outer walls extending from opposite sides of the connecting wall, wherein   the tank is coupled to the plurality of tubes such that the outer walls are disposed along outermost tubes that are stacked at outermost sides, wherein   the outer wall member is included in at least one of the outer walls of the tank, and the side wall member is included in the connecting wall of the tank.   
   
   
       13 . The heat exchanger according to  claim 12 , wherein the bulge extends over the outer walls of the tank. 
   
   
       14 . The heat exchanger according to  claim 1 , further comprising:
 at least one bypass tube defining a first fluid passage therein through which the first fluid flows and a thermal insulation area on its outer periphery, the bypass tube disposed in parallel to the plurality of tubes; and   a partition wall disposed between the tubes and the bypass tube to separate the thermal insulation area from an area where the second fluid flows.   
   
   
       15 . The heat exchanger according to  claim 14 , wherein
 the bypass tube has a main wall opposed to the partition wall,   the main wall of the bypass tube has a projection that projects toward the partition wall on its peripheral end and contacts the partition wall such that at least a part of the thermal insulation area is defined by a space provided between the main wall of the bypass tube and the partition wall and surrounded by the projection of the bypass tube.   
   
   
       16 . The heat exchanger according to  claim 14 , wherein
 one of the plurality of tubes, which is opposed to the partition wall, provides an opposed main wall opposed to the partition wall,   the opposed main wall has the projection, the first recess and the second recess, the projection projects toward the partition wall and is in contact with the partition wall such that a space is provided between the opposed main wall of the tube and the partition wall and surrounded by the projection of the tube, and   the space is in communication with the second fluid inlet part and the second fluid outlet part through the first recess and the second recess of the opposed main wall, respectively.   
   
   
       17 . The heat exchanger according to  claim 1 , further comprising:
 a first fluid inlet tank defining a first tank space and having an opening, the first fluid inlet tank coupled to the tubes such that first ends of the tubes are disposed in the opening of the first fluid inlet tank and the first tank space is directly in communication with the first fluid passages defined inside of the tubes,   a first fluid outlet tank defining a second tank space and having an opening, the first fluid outlet tank coupled to the tubes such that second ends of the tubes are disposed in the opening of the first fluid outlet tank and the second tank space is directly in communication with the first fluid passages defined inside of the tubes.