AU2008295434A1

AU2008295434A1 - A heat exchanger

Info

Publication number: AU2008295434A1
Application number: AU2008295434A
Authority: AU
Inventors: John Francis Urch
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-09-04
Filing date: 2008-09-01
Publication date: 2009-03-12
Anticipated expiration: 2028-09-01
Also published as: US20100224347A1; CN101821576A; AU2008295434B2; WO2009029976A1

Description

WO 2009/029976 PCT/AU2008/001301 1 A HEAT EXCHANGER Technical Field The present invention relates to heat exchangers and more particularly to heat exchangers through which a number of fluid streams past for the transfer of heat 5 therebetween, and more particularly but not exclusively to heat exchangers employed in air conditioning apparatus and water distillation apparatus. Background of the Invention Described in International Patent Publication W003,18360, USA patents 6829900, 6935132 and 5829513 as well as Australian Patent applications 2004215315 10 and 2005266840 are various heat exchanger apparatus and air conditioning apparatus. Heat exchangers described in the above patent documents, as well as available heat exchangers of similar constructions suffer from the disadvantage that they suffer from a loss of efficiency due to the restriction to the flow of fluid (gas) therethrough. Object of the Invention 15 It is the object of the present invention to overcome or substantially ameliorate the above disadvantage. Summary of the Invention There is disclosed herein a heat exchanger frame of generally rectangular configuration having two opposite sides, said frame having a plurality of baffles that 20 extend between the opposite sides so as to provide a plurality of passages extending between the opposite sides, and wherein each baffle includes a longitudinally central portion that extends longitudinally generally diagonally relative to said opposite sides. Preferably, each central portion extends at an acute angel relative to or of said sides. 25 Preferably, each central portion extends at approximately 450 to said opposite sides. Preferably, the central portions are each generally linear. There is further disclosed herein a heat exchanger including: a plurality of stacked frames, each frame being of a rectangular configuration so 30 as to have four sides, a plurality of baffles extending between two opposite sides of said four sides so that adjacent baffles defining a passage extending between said opposite sides; WO 2009/029976 PCT/AU2008/001301 2 a sheet material located between adjacent frames and covering the passages of the adjacent frames and providing for the transfer of heat between fluid passing between the passages of adjacent frames; and wherein a plurality of the passages of each frame include an entry passage portion, a 5 generally central passage portion and an exit passage portion, with the generally central passage portion extending diagonally relative to said opposite sides. Preferably, in respect of each passage, arcuate passage portions join the entry passage portion and the exit passage portion to the central passage portion. Preferably, said central passage portion extends at approximately 450 to said 10 opposite sides. Preferably, each of said opposite sides includes a first side portion and a second side portion, with the first side portions being located directly opposite each other, and the second side portions being located directly opposite each other and wherein in respect of each passage of said plurality of passages, the inlet portions extending from a first one of is the first side portions, and the exit portions extending from the second side portion of the other opposite side. Preferably, each side portion extends approximately half the length of the respective side. Preferably, said entry portions and said exit portions extend generally normal to 20 their respective side. Preferably, said frames are arranged so that the central passage portions of adjacent frames are substantially perpendicular. Preferably, said sheet material is substantially moisture impervious. In an alternative preferred form, preferably said sheet material is moisture 25 pervious. In a further preferred form, said sheet material is sheet Mylar (Registered Trademark). There is also disclosed herein an air conditioning apparatus having the above heat exchanger. 30 Preferably, said air conditioning apparatus includes water sprays to deliver water to at least some of said passage portions.

WO 2009/029976 PCT/AU2008/001301 3 Brief Description of the Drawings Preferred forms of the present invention will now be described by way of example with reference to the accompanying drawings wherein: Figure 1 is a schematic front view of a first air conditioning apparatus; 5 Figure 2 is a schematic side elevation of a second air conditioning apparatus; Figure 3 is a schematic front view of the apparatus of Figure 2; Figure 4 is a schematic sectioned side elevation of a third air conditioning apparatus; Figure 5 is a schematic sectioned side elevation of a fourth air conditioning 10 apparatus; Figure 6 is a schematic sectioned side elevation of a fifth air conditioning apparatus; Figure 7 is a schematic sectioned side elevation of a sixth air conditioning apparatus; 15 Figure 8 is a schematic parts exploded isometric view of a portion of a heat exchanger including frames and sheet materials to separate the frames; Figure 9 is a schematic sectioned end elevation of portion of the heat exchanger of Figure 8; Figure 10 is a schematic sectioned side elevation of portion of the heat exchanger 20 of Figure 8; Figure 11 is the schematic plan view of a frame employed in the heat exchanger of Figure 8; Figure 12 is a schematic end elevation of the frame of Figure 11; Figure 13 is a schematic end elevation of the frame of Figure 11; 25 Figure 14 is a schematic end elevation of the frame of Figure 11; Figure 15 is a schematic isometric view of a stack of the frames of Figure 11; Figure 16 is a schematic top plan view of the stack of Figure 15; Figure 17 is a schematic top plan view of a modification of the stack of Figure 15; 30 Figure 18 is a schematic isometric view of the stack of Figure 17; Figure 19 is a schematic sectioned elevation of a portion of a frame of the stack of Figure 17; Figure 20 is a schematic sectioned elevation of a portion of a frame of the stack of Figure 17; WO 2009/029976 PCT/AU2008/001301 4 Figure 21 is a schematic sectioned elevation of a portion of a frame of the stack of Figure 17; and Figure 22 is a schematic isometric view of a portion of the frame employed in the stack of Figure 17. 5 Detailed Description of the Preferred Embodiments In the accompanying drawings there is schematically depicted a heat exchanger 10. The heat exchanger 10 includes a plurality of heat exchanger frames 12 that are arranged in a stack 13, with adjacent frames separated by a length 14 of sheet material 15. The length 14 is arranged along a serpentine path so as to provide a plurality of pockets 10 16. Located in each pocket is a respective one of the frames 12. In this embodiment each of the frames 12 is of a rectangular configuration and more particularly a square configuration. The stack 13 is of a parallelepiped configuration. Each frame 12 is generally flat (generally planar) and in this embodiment is 15 square in configuration. Each frame 12 has four sides 16, 17, 18 and 19. The sides 17 and 19 are generally flat strips 21 and do not have any apertures. The opposite sides 16 and 18 each include a first side portion 22 or 23, and second side portions 24 or 25. The side portions 23 and 24 are also generally flat strips and do not have any apertures, while the side portions 22 and 25 each have a plurality of apertures 26 or 27. 20 Extending between the side portions 22 and 25 is a plurality of baffles 28 that are essentially strips or flanges, with a passage 29 being located between each adjacent pair of baffles 28. The baffles 28 are arranged so that each aperture 26/27 is aligned with a respective one of the passages 29. Preferably at least some of the passages 29 are divided longitudinally by a dividing baffle 30. Accordingly in operation a fluid can enter via one 25 of the apertures 26/27 and flow along the respective passage 29 to exit via the other aperture 26/27. The passages 29 of adjacent passages 29 are separated by the length 14. Support members 31 extend between the sides 17, 18, 19 and 20 to aid in supporting the baffles 28 and 30 in the positions illustrated. In that regard it should be appreciated the support members 31 do not block the passages 29. 30 Each of the passages 29 includes a first passage portion 32 that extends from the side portion 22. Each passage 29 further includes a second passage portion 33 that extends from the side portion 25. In that regard the passage portions 32 and 33 extend generally normal form the respective side portions 22 and 25.

WO 2009/029976 PCT/AU2008/001301 5 Each passage 29 further includes a diagonal generally central passage portion 34 that may be divided longitudinally by a respective one of the baffles 30. Each passage portion 34 is joined to its respective passage portions 32 and 33 by arcuate passage portions 35. As is best seen in Figure 11, each diagonal passage portion 34 extends at an 5 acute angle to at least one of the sides 16 or 18, and preferably at approximately 450 to the opposite sides 16 and 18. Accordingly at the passage portions 34 the baffles 28 and 30 also extend at approximately 45* to the sides 16 and 18. The portions 34 are also generally linear in longitudinal length. The side portions 22 and 25 are provided with projections 36 that would aid the 10 mounting thereto of ducting when the frames 12 are arranged in the stack 13. Preferably the sides 16 and 18 are provided with ridges 37 that are engaged with a corresponding longitudinal recess 38 of the next adjacent frame 12 to provide for the alignment of the frames 12 and there securing in a stack 13. As best seen in Figure 10, each frame 12 has a recess 38 within which the length 15 14 is located to be securely attached to the frames 12 by engagement of the ridges 37 on the recess 38. The stack 13 has four side faces 40 to 43, with the faces 41 and 43 having strips 21 so that they are essentially closed off. The faces 40 and 42 have the apertures 26 and 27 with the passages 29 extending therebetween so that fluid may flow between the faces 20 40 and 42. The stack 13 is particularly formed by a plurality of the frames 12, that are stacked as follows. Each alternate frame is arranged in the orientation as shown in Figure 11. Every other frame is arranged with the frame 12 as shown in Figure 11 but rotated through 180' about the transverse axis 44. Accordingly the stack 13 provides four face 25 portions, 45, 46, 47 and 48. The face portion 45 has apertures 26 as does the face portion 46. The face portions 47 and 48 have apertures 27. The passages 29 extending from the apertures 26 of face portion 46 communicate with the apertures 27 of the face portion 48. Simultaneously the passages 26 of the face portion 45 communicate with the apertures 27 of the face portion 47. Accordingly the diagonal passage portions 34 of adjacent frames 30 12 are generally perpendicular. Because the length 14 is interposed between adjacent frames 12, the passages 29 of adjacent frames 12 do not communicate in respect of fluid flow however there is transfer of heat between adjacent passages 29 of adjacent frames 12. For example, a fluid could enter the apertures 26 of the face 46 and travels through the passages 29 to exit via 35 the apertures 27 in the face 42, while a fluid entering the apertures 27 of the face portion WO 2009/029976 PCT/AU2008/001301 6 47 would flow via passages 29 to the apertures 26 of the face portion 45, to provide for the transfer of heat from fluid passing from face portion 46 to face portion 48 to fluid passing from face portion 47 to face portion 45. Accordingly the passages 29 extending between the face portions 46 and 48 5 provide a first fluid path, while the passages 29 extending between the face portions 45 and 47 provide a second fluid path. The face portions 45, 46, 47 and 48 are generally planar with the apertures 26 and 27 arranged in linear rows. The rows of face portion 45 are offset relative to the rows of face portion 46, while the rows of face portion 48 are offset relative to the rows of face 10 portion 47. As is best seen in Figure 16, the diagonal portions 34 of adjacent frames 12 are generally perpendicular. Marked in Figure 16 are two diagonal passage portions 34, as can be seen they are generally perpendicular. In the embodiment of Figures 17 to 31, the stack 13 is modified, in particular 15 each of the frames 12 is provided with flanges 49 that are arranged in rows to provide for engagement of manifolds with the stack 13 for the flow of fluid to and from with respect to the stack 13. As is best seen in Figures 19 and 20, the corners of the frame 12 are either provided with a passage 170 or a pin 171, with the pins 171 being received within the 20 passage 170 of the next adjacent frame to thereby secure adjacent frames 12 together. To aid in sealingly connecting adjacent frames around the periphery of each frame 12 there is provided a ridge 172 and a recess 173 with the ridge 172 received within the recess 173 of the next adjacent frame 12. Where two recesses 173 are located adjacent, a sealing element 174 is located therein to again sealingly connect the adjacent 25 frames 12. In Figure 1 there is schematically depicted an air conditioning apparatus 50. Typically the apparatus 50 is intended to be installed in a roof 51 that separates the building interior 53 from the building exterior 54. The apparatus 50 includes a housing 52 within which there are two heat 30 exchangers 10 (as described with reference to Figures 8 to 16), each heat exchanger 10 providing two air paths 55 and 56. As an example the air paths 55 may be provided by the passages 29 extending from the face portion 45 to the face portion 47, while the paths 56 may be provided by the passages 29 extending from the face portion 48 to the face portion 46.

WO 2009/029976 PCT/AU2008/001301 7 The housing 52 provides inlets 57 through which air enters from the interior 53 to be exhausted to the exterior 54 via outlets 58. The housing 52 provides further inlets 59 that take air from the exterior 54, with that air being delivered to the interior 53 via outlet 60. Located just upstream of the outlets 60 is a fan 61 that draws air from the 5 passages 56 and delivers that air under pressure to the outlets 60. Accordingly air is taken from the exterior 54 through the filters 62 and delivered to the paths 56. Also located adjacent the outlets 60 is a heater 63 that is operable to heat air being delivered to the interior 53 via the outlets 60. Also located internally of the housing 52 are nozzles 64 that produce a water 10 mist (spray) that is delivered to the face portions 45, with water being drawn into the path 55 to cool the air passing therethrough. The cooled air passing through the path 55 cools the air passing through the path 56 to thereby lower the temperature of the air entering the interior 53. If so required further nozzles may direct water sprays at the faces 47, with water droplets entering the path 55 again to aid in cooling the air passing therethrough. 15 A filter 66 inhibits water exiting to the exterior 54. Water is collected adjacent lower portions 67 to provide a reservoir for pumps 68 that deliver water under pressure to the nozzles 64 and 65. There would also be a means of supplying water to the pumps to maintain a required level for operation of the pumps 68. In operation of the above apparatus 50, air from the exterior 54 is cooled and 20 delivered to the interior 53 when the temperature of the air in the interior 53 is to be lowered. However under cold conditions, the heater 63 could be operated to raise the temperature of air being delivered to the interior 53. Adjacent the outlets 58, there is provided a fan 69 that draws air through the paths 55 to thereby take air from the interior 53. 25 In Figures 2 and 3 there is schematically depicted an air conditioning apparatus 70. Typically the apparatus 70 would be mounted adjacent a wall 88 separating the interior 71 from the exterior 72 of a building. The apparatus 70 includes a housing 74 that includes a pair of heat exchangers 10. Again the heat exchangers 10 are in accordance with the heat exchanger described previously. 30 In this embodiment the heat exchangers 10 provide paths 75 and 76, with the paths 76 extending between face portions 48 and 46, and the paths 75 extending between face portions 47 and 45. The housing 74 has an inlet 77 from which air is drawn by the fan 78. The fan 78 delivers air under pressure to the paths 75 that ultimately deliver the air to outlets 79 35 that exhaust air to the exterior 72. A nozzle 80 receives water under pressure to deliver a WO 2009/029976 PCT/AU2008/001301 8 water spray to the paths 75 to cool the air passing therethrough, so that air passing through the paths 76 is cooled thereby. The housing 72 further includes inlets 81 that provide for the delivery of air to the path 76 via filters 82. Air is drawn through the paths 76 via a fan 83, which fan 83 5 delivers air to an outlet 84 via which air is delivered to the interior 71. A heater 85 is also provided should the air being delivered to the outlet 84 require heat. The housing 74 has lower portions 86 that provide a reservoir for pumps 87 that deliver water under pressure to the nozzle 80. In operation of the above described apparatus 70, air passing along the paths 75 10 is cooled by air being delivered thereto via the nozzle 80. This cool air then cools the air passing along the paths 76 that is ultimately delivered to the interior 71 via the outlet 84. In Figure 4 there is schematically depicted an air conditioning apparatus 10 mounted on the exterior of a wall 91 of a building. The wall 91 separates the interior 92 from the exterior 93. The apparatus 90 includes a housing 94. Located internally of the 15 housing 94 is a heat exchanger 10 as previously described. The housing 94 provides an inlet 95 that takes air from the interior 92, with the air being delivered via fan 96 to path 97 of the heat exchanger 10. The path 97 delivers the air to an outlet 98. A nozzle 99 delivers a stream of water spray to the path 97 to cool the air passing along the path 97. The housing 94 has a further inlet 100 that takes air from the exterior. A fan 101 20 takes the air from the inlet 100 and delivers it to a path 102 wherefrom the air is delivered to an outlet 103, the outlet delivering cool air to the interior 92. The cooled air passing along the path 97 cools the air passing along the path 102. A lower portion 104 provides a reservoir for water to be taken by the pump 105 that delivers water under pressure to the nozzle 99. 25 If so required a heater 106 is provided just upstream of the outlet 103 and is operable to heat air delivered to the outlet 103 if so required. As an example, the path 97 may be a plurality of the passages 29 extending from the face portion 47, with the path 97 extending to the face portion 45. The path 102 could be a plurality of the passages 29 extending from the face portion 48, with the path 102 extending to the face portion 46. 30 In the embodiment of Figure 5 there is schematically depicted an air conditioning apparatus 110. The apparatus 110 is mounted on a wall 111 separating the interior 112 from the exterior 113. The apparatus 110 has a housing 114 providing an inlet 115 that takes air from the interior 112 and delivers it to a fan 116. The fan 116 delivers air under pressure to the path 117 of the heat exchanger 10. From there the air is delivered to an 35 outlet 118, exhausting the air to the exterior 113.

WO 2009/029976 PCT/AU2008/001301 9 The housing 114 provides a second inlet 119 that delivers air via a filter 120 to the path 121. The fan 122 draws air through the path 121 and delivers it to an outlet 123, the outlet 123 delivering the air to the interior 112. A nozzle 124 delivers a stream of water spray to the path 117 to cool the air 5 passing therethrough so that air passing along the path 121 is cooled before being delivered to the outlet 113 and therefore the interior 112. A heater 125 is operable to heat the air being delivered to the outlet 123. The housing 114 provides a lower portion 126 that provides a reservoir for a pump 127 that delivers water under pressure to the nozzle 124. 10 In Figure 4 it should be noted air passes along the paths 97 and 102 in the same general direction across the heat exchanger 10. However in the embodiment of Figure 5, the air passes in opposite directions along the paths 117 and 121 through the heat exchanger 10. In Figure 6 there is schematically depicted an air conditioning apparatus 130. 15 The apparatus 130 is mounted on a wall 131 that separates the interior 132 from the exterior 133. The apparatus 130 has a housing 134 providing an inlet 135 that takes air from the interior 132 and delivers it to the heat exchanger 10. The heat exchanger 10 has a path 136 that delivers the air to a fan 137. Located downstream of the path 136 is a 20 nozzle 138 that directs a water spray to the path 136 so that water flowing along the path 136 will cool air passing therethrough. A filter 139 inhibits water being drawn into the fan 137. The housing 134 has a second inlet 139 that delivers air to the path 140 via a filter 141. The path 140 leads to a fan 142 that delivers air to a first outlet 143 25 communicating with the interior 132 and a further outlet 144 leading to a duct 145 that delivers conditioned air to another remote location. Typically the path 136 would extend between face portion 46 and face portion 48, while the path 140 would extend from face portion 45 to face portion 47. The housing 134 has a lower portion 146 that provides a water reservoir for a 30 pump 147 that delivers water under pressure to the nozzle 138. In operation of the above described apparatus 130, air passing along the path 136 is cooled via the water evaporating therein, thereby cooling the air passing along the path 140 to be delivered to the interior 130. A heater 148 is operable to heat the air being delivered to the outlets 143 and 35 144.

WO 2009/029976 PCT/AU2008/001301 10 Air passing along the paths 136 and 140 passes in the same general direction across the heat exchanger 10. In Figure 7 there is schematically depicted an apparatus 150. The apparatus 150 is located at the exterior 151 of a building. In this embodiment the apparatus 150 has a 5 housing 152 that provides an inlet 153 that takes air via a duct 154 from the interior 151 of the building. Air from the inlet 153 is delivered via a fan 155 to the path 156 of the heat exchanger 10. A nozzle 158 delivers water spray to the path 156 to cool the air passing therethrough. The housing 152 provides an inlet 159 that takes air from the exterior 151, for 10 delivery to the path 160 of the heat exchanger 10. The path 160 delivers air to a fan 161 that via an outlet 164 delivers air to a duct 162 extending to the interior of the associated building. A heater 163 is operable to heat the air being delivered to the duct 162. The housing 152 includes a lower portion 165 that provides a water reservoir for a pump 166 that delivers water under pressure to the nozzle 158. is In operation of the above described apparatus 150, air entering the path 156 is cooled by the water evaporating therein, to thereby cool air passing along the path 160. Typically the path 160 would extend between face portion 46 and face portion 48, while the path 156 extends from the face portion 47 to the face portion 45. As can be seen from Figure 7 air passing along the paths 156 and 160 travel basically opposite 20 directions across the heat exchanger 10. The material 15 of the length 14 provides for the transfer of heat between adjacent passages 29 of adjacent frames 12. In that regard, the material 15 is preferably Mylar (Registered Trade Mark). However the material 15 may prevent or may provide for the transfer of moisture between adjacent passages 29 of adjacent frames 12.

Claims

1. A heat exchanger frame of generally rectangular configuration having two opposite sides, said frame having a plurality of baffles that extend between the opposite sides so as to provide a plurality of passages extending between the opposite 5 sides, and wherein each baffle includes a longitudinally central portion that extends longitudinally generally diagonally relative to said opposite sides.

2. The frame of claim 1, wherein each central portion extends at an acute angel relative to or of said sides.

3. The frame of claim 1, wherein each central portion extends at 10 approximately 450 to said opposite sides.

4. The frame of claim 1, 2 or 3, wherein the central portions are each generally linear.

5. A heat exchanger including: a plurality of stacked frames, each frame being of a rectangular configuration so is as to have four sides, a plurality of baffles extending between two opposite sides of said four sides so that adjacent baffles defining a passage extending between said opposite sides; a sheet material located between adjacent frames and covering the passages of the adjacent frames and providing for the transfer of heat between fluid passing between 20 the passages of adjacent frames; and wherein a plurality of the passages of each frame include an entry passage portion, a generally central passage portion and an exit passage portion, with the generally central passage portion extending diagonally relative to said opposite sides.

6. The heat exchanger of claim 5, wherein in respect of each passage, 25 arcuate passage portions join the entry passage portion and the exit passage portion to the central passage portion.

7. The heat exchanger of claim 5 or 6, wherein said central passage portion extends at approximately 450 to said opposite sides.

8. The heat exchanger of claim 5, 6 or 7, wherein each of said opposite 30 sides includes a first side portion and a second side portion, with the first side portions being located directly opposite each other, and the second side portions being located directly opposite each other and wherein in respect of each passage of said plurality of passages, the inlet portions extending from a first one of the first side portions, and the exit portions extending from the second side portion of the other opposite side. WO 2009/029976 PCT/AU2008/001301 12

9. The heat exchanger of claim 8, wherein each side portion extends approximately half the length of the respective side.

10. The heat exchanger of the entry portions and the exit portions extend generally normal to their respective side. 5

11. The heat exchanger of any one of claims 5 to 10, wherein the frames are arranged so that the central passage portions of adjacent frames are substantially perpendicular.

12. The heat exchanger of any one of claims 5 to 11, wherein said sheet material is substantially moisture impervious. 10

13. The heat exchanger of any one of claims 5 to 10, wherein said sheet material is moisture pervious.

14. The heat exchanger of claim 12, wherein said sheet material is sheet Mylar (Registered Trademark).

15. An air conditioning apparatus having the above heat exchanger. 15

16. The apparatus of claim 15, further including water sprays to deliver water to at least some of said passage portions.