A COOLING TOWER

Technical Field

The present invention relates to combinations to provide cooled water for the purpose of removing heat from a process or system and more particularly but not exclusively to assemblies including a condenser to which refrigerant is delivered to condense therein, such as a condenser of an air conditioning system or a refrigeration system, and a sub assembly to aid in removing heat from the condenser.

Background of the Invention

The present invention relates to what is traditionally known as a "cooling tower", That is, an arrangement that provides cooled water for the purposes of removing heat from a processor system such as cooling condensers of air conditioning systems and refrigeration systems.

The abovementioned cooling towers suffer from the disadvantage that the water employed is open to atmosphere with the result that if the system is not correctly maintained it can become a source of legionnaires disease. A further disadvantage of these towers is their high water consumption.

Object of the Invention

It is the object of the present invention to overcome or substantially ameliorate at least one of the above disadvantages.

Summary of the Invention

There is disclosed herein a device from which heat is to be extracted, and a sub assembly to provide cooled water to aid in removing heat from the device, said sub assembly including: a heat exchanger having a plurality of stacked frames, each frame providing a plurality of passages, with adjacent frames being separated by sheet material providing for heat transfer between adjacent passages of adjacent frames, the passages being arranged in a first set and a second set, the first set being provided to receive air and the second set being provided to receive water, with each set having an inlet and an outlet; a spray assembly to deliver water spray to said first set to cool air passing therethrough to thereby cool the water passing through said second set; a first duct, said first duct being connected to the inlet of said second set and operatively associated with said device;

a second duct, said second duct being connected to the outlet of said second set and also operatively associated with said device so that cooled water passing from the second duct to the first duct removes heat from said device; and wherein the cool water circulates in a closed loop at least partly provided by said device and sub assembly.

Preferably, said sub assembly includes an upstream chamber to which air is delivered under pressure, said upstream chamber being upstream of and in communication with the inlet of said first set so as to deliver air thereto, with said spray assembly being located in said chamber so as to deliver water spray to the inlet of said first set to aid in cooling air passing along said first set.

Preferably, said sub assembly includes a downstream chamber adjacent the outlet of said first set and a spray assembly in said downstream chamber to deliver water spray to the outlet of said first set to aid in cooling air passing along said first set.

Preferably, air is delivered under pressure to said upstream chamber by a fan. Preferably, said device has a water inlet and a water outlet, with the device water outlet being connected to the second set inlet by said first duct so as to deliver water thereto, and the device water inlet being connected to the second set outlet by said second duct so as to receive water therefrom.

Preferably, said heat exchanger is a primary heat exchanger and said device has a housing with the device water inlet and the device water outlet, with a further heat exchanger located in the housing, with a fluid to passing through said further heat , exchanger, with water passing from the device water inlet past the further heat exchanger to the device water outlet to cool the further heat exchanger and therefore said fluid.

Preferably, said device is a condenser of an air conditioning or a refrigeration system, and said further heat exchanger is a condenser heat exchanger to which a refrigerant is delivered.

Preferably, said device is a condenser of an air conditioning or a refrigeration system, and said further heat exchanger is a condenser coil to which a refrigerant is delivered. Preferably, the combination further includes a condenser of a refrigeration or air conditioning system, with said fluid being an intermediate fluid that passes the further heat exchanger for delivery to said condenser to cool the condenser.

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 side elevation of an assembly including a condenser of an air conditioning system and a sub assembly to deliver cooled water to the condenser;

Figure 2 is a schematic side elevation of a modification of the assembly of Figure 1 ;

Figure 3 is a schematic parts exploded isometric view of a portion of a heat exchanger including frames and sheet materials to separate the frames; Figure 4 is a schematic sectioned end elevation of portion of the heat exchanger of Figure 3;

Figure 5 is a schematic sectioned side elevation of portion of the heat exchanger of Figure 3;

Figure 6 is the schematic plan view of a frame employed in the heat exchanger of Figure 3;

Figure 7 is a schematic end elevation of the frame of Figure 6;

Figure 8 is a schematic end elevation of the frame of Figure 6;

Figure 9 is a schematic end elevation of the frame of Figure 6;

Figure 10 is a schematic isometric view of a stack of the frames of Figure 6; Figure 11 is a schematic top plan view of the stack of Figure 10;

Figure 12 is a schematic side elevation of an assembly including a condenser of a refrigeration system and a sub assembly to deliver cooled water the condenser; and

Figure 13 is a schematic side elevation of a modification of the assembly of Figure 12.

Detailed Description of the Preferred Embodiments

In the following embodiments the device to be cooled is the condenser coil of a refrigeration or air conditioning system. However the device to be cooled can be any device from which heat needs to be extracted during operation of the device. As a further example, the device may be the mould of an injection moulding machine. In Figure 1 there is schematically depicted an assembly 50. The assembly 50 includes a condenser 51 of an air conditioning system to which a compressed refrigerant is delivered so that the refrigerant condenses as a result of heat being removed therefrom.

The condenser 51 has an outer housing 78 that receives the cooled water and within which there is located a condenser coil 79 so as to be at least partly submerged in the water.

The condenser 51 receives water cooled by a sub assembly 52. The sub assembly 52 has cool water outlets 53 that communicate with water inlets 54 of the condenser 51. The condenser 51 has outlets 55 that communicate with water inlets 56 of the sub assembly 52. The coil 79 receives the refrigerant to be condensed.

Ducting 57 connects the outlets 53 with the inlets 54 while ducting 58 connects the outlets 55 with the inlets 56. The sub assembly 52 includes a cabinet 59 within which there is located primary heat exchangers 60. The heat exchangers 60 may be a heat exchanger as described in USA Patent 6,829,900, International Patent Applications PCT/AU01/00273, PCT/AU2004/000103, PCT/AU2005/001097, PCT/AU2008/001299,

PCT/AU2008/001301 and PCT/AU2008/001300. The heat exchanger 60 provides a first a set of passages 61, and a second set of passages 62. The passages 61 provide for the flow of air through the heat exchanger 60, while the passages 62 provide for the flow of water through the heat exchanger 60.

The passages 60 have an inlet 63 and an outlet 64 while the passages 62 have an inlet 65 and an outlet 66. The inlet 63 receives air under pressure from a chamber 67, with the air being delivered thereto under pressure by means of a fan 68. Also located in the chamber 67 are spray nozzles 69 that deliver water spray 70 to the inlets 63 so that air passing along the passages 61 is cooled by the water spray. The outlet 64 communicates with a chamber 71 via which air exits via an air outlet 72. The passages 61 communicate with water receiving chambers 73 and 74, that are provided with the outlets 53 and inlets 56. Due to air passing through the passages 61 being cooler than water passing through the passages 62, water passing through the passages 62 is cooled, thereby providing for the delivery of cooled water to the condenser 51.

Preferably pumps 75 circulate water through the closed system including passages 62, chamber 74, outlet 53, ducting 57, condenser 51 and ducting 58.

Preferably the chamber 71 has a reservoir 76 that collects water leaving the passages 61, and via a pump 77 returns the water to the nozzles 69. Due to water evaporation a means of delivering "top up" water to the chambers 71 is provided.

In Figure 2, there is schematically depicted a modification of the assembly 50 of Figure 1. In this embodiment there is a single chamber 67 and a single chamber 71 as well as a single chamber 73.

In the embodiment of Figure 2, the primary heat exchanger is provided by the heat exchanger 10 that will now be described.

In Figures 3 to 11 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 16. Located in each pocket is a respective one of the frames 12. In this , embodiment the sheet material 15 resists the flow of water through the material 15. Preferably the material 15 is "Mylar" (Registered Trade Mark).

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 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.

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 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.

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.

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 s approximately 45° 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 side portions 22 and 25 are provided with projections 36 that would aid the 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 witho 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 14 is located to be securely attached to the frames 12 by engagement of the ridges 37 on the recess 38. s 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 40 and 42.

The stack 13 is particularly formed by a plurality of the frames 12, that are0 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 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 ₅ 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 12 are generally perpendicular.

Because the length 14 is interposed between adjacent frames 12, the passages 290 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 the apertures 27 in the face 42, while a fluid entering the apertures 27 of the face 47 would flow via passages 29 to the apertures 26 of the face 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 provide the first fluid path consisting of passages 61, while the passages 29 extending between the face portions 45 and 47 provide the second fluid path consisting of passages 62.

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 portion 47.

As is best seen in Figure 11, the diagonal portions 34 of adjacent frames 12 are generally perpendicular. Marked in Figure 11 are two diagonal passage portions 34, as can be seen they are generally perpendicular.

In Figure 12 there is schematically depicted an assembly 100 that includes a condenser 101 of a refrigeration system to which a compressed refrigerant is delivered so that the refrigerant condenses as a result of heat being removed therefrom. The condenser

101 includes an outer housing 102 that provides a chamber 103 that receives cooled water to remove heat from the condenser coil (refrigerant heat exchanger) 104. The condenser coil 104 has an inlet 105 and an outlet 106 via which the refrigerant passes through the coil 104.

The condenser 101 receives water cooled by a sub assembly 107. The sub assembly 107 includes a cabinet 108 within which there is located a primary heat exchanger 109. The heat exchanger 109 may be a heat exchanger such as the heat exchanger 60 of the earlier embodiments. The heat exchanger 109 provides a first set of passages 110, and a second set of passages 111. The passages 110 provide for the flow of air through the heat exchanger 109, while the passages 111 provide for the flow of water through the heat exchanger 109.

The passages 110 have an inlet 112 while the passages 111 have an inlet 113. The passages 110 have an outlet 114 while the passages 111 have an outlet 115. The inlet 112 receives air from a chamber 116 that takes air from a vent 117 in the cabinet 108. That is, the inlet 112 receives air from the exterior. Also delivered to the inlet 112 is a water mist provided by a nozzle 118 that receives water under pressure from a pump 119 that takes water from the lower end of the chamber 116.

A water mist can also be delivered to the outlet 114 by a nozzle 120, that again receives water under pressure from the pump 119. Water entering the passages 110 via

the inlet 112 and outlet 114 cools the air passing along the passages 110 by at least partial evaporation of the water entering the passages 1 10.

The inlet 113 communicates with a chamber 121 that receives water, with the water then passing along the passages 111 to the chamber 103. Water passing along the passages 111 is cooled by the air passing along the passages 110, accordingly the chamber 103 receives cooled water. Water is taken from the chamber 103 by pump 122 and returned to the chamber 121. Accordingly the cold water that passes through the chamber 103 takes heat from the coil 104, with the water then returned to the chamber 121 from where it again passes along the passages 112 to be again cooled. Air is drawn through the passages 110 by means of a fan 123 that exhausts the air to the exterior. Between the fan 123 and the chamber 124 containing the nozzle 120 is a pad 125 that at least minimises any spray delivered to the exterior by the fan 123.

In Figure 13 there is schematically depicted an assembly 200 that is essentially a doubling of the assembly 100. Accordingly the same reference numerals have been used. However in this embodiment, the two primary heat exchangers 109 both provide cooled water for a single condenser 101. There is also only a single fan 123 and pad 125. In respect of the embodiments of Figures 12 and 13 it should be appreciated that they are described with reference to a refrigeration system, however they could also been incorporated in an air conditioning system with the condenser 101 being the condenser of the air conditioning system.

In the embodiments of Figures 12 and 13, the coil 104 may not be a condenser coil but merely a coil through which an intermediate fluid passes to be cooled and delivered via the outlet 106 to the condenser, and returned via the inlet 105. Accordingly the coil 104 is a heat exchanger operatively associated with the condenser to remove heat therefrom.

In the above described embodiments, the primary heat exchangers are preferably a heat exchanger as described in International Patent Application PCT/AU2008/001301, that is a heat exchanger in which the stacked frames and separating sheet material are sealingly connected so that water does not escape from the passages along which the water passes.

The above preferred embodiments have the advantage that the water circulating through the primary heat exchangers is not exposed to atmosphere, that is the water circulated within the sub assembly is circulated in a closed system.