Heat Exchanger

Abstract

A heat exchanger ( 15 ) comprising a plurality of generally parallel passages through which air is to pass in a first direction through a first set of passages ( 16 ) and in an opposite direction to said first direction through a second set of said passages ( 22 ), the passages of said first set ( 16 ) being located adjacent the passages of said second set ( 22 ). The heat exchanger ( 15 ) further comprising sheet material that separates the first set ( 16 ) from the second set ( 22 ), and provides for the transfer of heat between said first set ( 16 ) and said second set of passages ( 22 ).

1 . A heat exchanger including:
 a plurality of generally parallel passages through which air is to pass in a first direction through a first set of said passages and in an opposite direction to said first direction through a second set of said passages, the passages of said first set being located adjacent the passages of said second set;   sheet material separating the first set from the second set, and providing for the transfer of heat between said first set and said second set of passages; and   wherein the passages of at least one of the sets each have a first length, the first lengths including co-extensive length portions, and a second length with the air passing through the passages changing in direction when passing between the first and second lengths, and said apparatus includes flow restriction means in at least some of the passages of said at least one of the sets.   
     
     
         2 . The heat exchanger of  claim 1 , wherein the flow restriction means are arranged so that the time required for air to pass through the passages of the at least one set is substantially the same. 
     
     
         3 . The heat exchanger of  claim 1 , wherein the first lengths extend longitudinally generally normal to the second lengths, with the first lengths being joined to the second lengths by arcuate portions. 
     
     
         4 . The heat exchanger of  claim 1  wherein the flow restriction means are located in at least some of the arcuate portion. 
     
     
         5 . The heat exchanger of  claim 1 , wherein said flow restriction means are located at end portions of said passages. 
     
     
         6 . The heat exchanger of  claim 1 , wherein said heat exchanger is a sensible heat exchanger with said sheet material inhibiting the transfer of moisture between the sets. 
     
     
         7 . The heat exchanger of  claim 6 , wherein said sheet material is foil or plastic material film. 
     
     
         8 . The heat exchanger of  claim 1 , wherein said heat exchanger is an enthalpy heat exchanger with said sheet material provides for the transfer of moisture between the sets. 
     
     
         9 . The heat exchanger of  claim 8 , wherein said sheet material is paper or cloth. 
     
     
         10 . The heat exchanger of  claim 1 , wherein said heat exchanger includes a plurality of stacked frames, each frame providing a respective one of the sets, with adjacent frames being separated, and each frame includes a plurality of generally parallel walls separating the passages. 
     
     
         11 . The heat exchanger of  claim 10 , wherein sheet materials separate the frames. 
     
     
         12 . The heat exchanger of  claim 1 , wherein each passage has a substantially constant transverse cross-section, with the flow restriction means being a reduction in the cross section. 
     
     
         13 . A frame for a heat exchanger, the frame being generally planar and including a plurality of generally parallel walls that are transversely spaced to provide a plurality of passages through which air passes to pass through the frame, each passage including a first length that extends to a second length with the first lengths having coextensive portions, and wherein the first lengths are longitudinally inclined to the second lengths, and at least some of the passages have a flow restriction means. 
     
     
         14 . The frame of  claim 13 , wherein each passage has a substantially constant cross-section, with the flow restriction means being a reduction in the cross-section. 
     
     
         15 . The frame of  claim 13 , wherein the flow restriction means is a projection that projects into the passages to reduce the transverse cross section thereof. 
     
     
         16 . The frame of  claim 13 , wherein the flow restriction means is a web that varies thickness and that extends across said walls. 
     
     
         17 . The frame of  claim 13 , wherein said frame is moulded from plastics material. 
     
     
         18 . The frame  claim 13 , wherein said first lengths extend at approximately 90° to said second lengths. 
     
     
         19 . The frame of  claim 13 , wherein the parallel walls are joined by longitudinal end walls so that in transverse cross section the parallel walls and end walls are of a sinusoidal configuration. 
     
     
         20 . The frame of  claim 13 , wherein the flow restriction means aid in maintaining equal dwell time for air passing through the co-extensive portions. 
     
     
         21 . An air conditioning apparatus including:
 a hollow body having a longitudinal side extending between opposite first and second ends;   a heat exchanger located in said body between said ends, the heat exchanger including a first set and a second set of passages, with each passage having an inlet opening and an outlet opening, with the inlet openings of each set being adjacent so as to be arranged in a group, each group being located adjacent said side so that the passages extending from the inlet openings thereof toward said first end, and the passages of said second set extending from the inlet openings thereof to said second end;   a first fan, said first fan being at said first end and drawing air from first set of passages;   a second fan, said second fan being located at said second end and drawing air from said second set of passages; and   wherein said first set of passages is provided to take air from within a room, with the air then being delivered by said first fan to outside the room, and said second set of passages is being provided to take air from outside the room, which air is then delivered by said second fan to said room.   
     
     
         22 . The apparatus of  claim 21 , wherein said inlet openings are located in a plane, said plane being generally parallel to said side. 
     
     
         23 . The apparatus of  claim 21 , wherein a filter is located to filter air delivered to said first set of passages. 
     
     
         24 . The apparatus of  claim 23 , wherein said side is provided with a panel displaceable to provide access to said filter. 
     
     
         25 . The apparatus of  claim 21 , wherein said housing has a first inlet extending to a first duct, said first duct extending to the inlet openings of said first passages. 
     
     
         26 . The apparatus of  claim 21 , wherein said housing has an outlet through which air is delivered to said room, said outlet communicating with said first fan. 
     
     
         27 . The apparatus of  claim 21 , wherein said body has a further inlet that delivers air to a further duct, said further duct providing air to said second set passages. 
     
     
         28 . An installation including:
 a building having a room and an enclosed roof cavity; and   an air conditioning apparatus including a heat exchanger having a first set of passages and a second set of passages, the passages being arranged for heat transfer between the two sets, said first set extending from an inlet that receives air from the room to an outlet communicating with said cavity, with said second set extending from an inlet positioned outside said cavity and room to an outlet delivering air to said room, and water delivery means to deliver water to said first set to cool the air passing therethrough to thereby cool air passing through said second set so that cooled air is delivered to said room.   
     
     
         29 . The installation of  claim 28 , wherein said water delivery means includes a nozzle assembly to deliver a water mist to said first set. 
     
     
         30 . The installation of  claim 29 , wherein said water delivery means includes a pad to which water is delivered and through which air passes to be delivered to said first set so that air leaving said pad is cooled. 
     
     
         31 . The installation of  claim 29 , wherein said pad saturates air passing therethrough. 
     
     
         32 . The installation of  claim 28 , wherein said heat exchanger is a sensible heat exchanger. 
     
     
         33 . The assembly of  claim 28 , wherein said air conditioning apparatus includes a heating means is operable to heat the air delivered to said room from the second set. 
     
     
         34 . The installation of  claim 33 , wherein said heating means includes tubes through which heated water passes. 
     
     
         35 . The installation of  claim 34 , wherein said installation further includes a solar hot water heater that delivers heated water to said heating means. 
     
     
         36 . The installation of  claim 28 , wherein said installation includes a first fan to cause air to pass through said first set and a second fan to cause air to pass through said second set. 
     
     
         37 . The installation of  claim 36 , wherein the fans are driven by electric motors. 
     
     
         38 . The installation of  claim 37 , wherein said installation includes a solar cell assembly that delivers electric current to the fans to drive the fans. 
     
     
         39 . An air conditioning apparatus including:
 a hollow body having an upper end and a lower end;   a heat exchanger located in the body between said ends, the heat exchanger including a first set and a second set of passages, the passages being arranged for heat transfer between the two sets, each set extending from an air inlet to an air outlet, with the inlet of said first passages being higher than the outlet of said first passages;   means to deliver water to the inlet of said first set to cool air passing from the first set inlet to the first set outlet; and   water collection means to collect any water leaving the first set outlet.   
     
     
         40 . The apparatus of  claim 39 , further including a pump means to deliver the water from the water collection means to said water delivery means. 
     
     
         41 . The apparatus of  claim 39 , wherein said water delivery means is a spray nozzle assembly. 
     
     
         42 . The apparatus of  claim 40 , wherein said water delivery means includes a pad, with air passing through said pad and then a water droplet stream issuing from said nozzle assembly with the air then delivered to said first set inlet. 
     
     
         43 . An installation including:
 a building including a room;   the air conditioning apparatus of  claim 39 , and   wherein said first set inlet receives air from said room and said first set outlet delivers air to outside said room, and said second set inlet receives air from outside said room and said second set outlet delivers air to said room so that air delivered to said room is cooled by air passing through said first set.   
     
     
         44 . The installation of  claim 43 , wherein said installation includes a ceiling cavity, and air from said first set outlet is delivered to said cavity. 
     
     
         45 . The heat exchanger of  claim 2 , wherein the first lengths extend longitudinally generally normal to the second lengths, with the first lengths being joined to the second lengths by arcuate portions. 
     
     
         46 . The heat exchanger of  claim 45 , wherein the flow restriction means are located in at least some of the arcuate portion. 
     
     
         47 . The heat exchanger of  claim 46 , wherein said flow restriction means are located at end portions of said passages. 
     
     
         48 . The heat exchanger of  claim 47 , wherein said heat exchanger is a sensible heat exchanger with said sheet material inhibiting the transfer of moisture between the sets. 
     
     
         49 . The heat exchanger of  claim 48 , wherein said sheet material is foil or plastic material film. 
     
     
         50 . The heat exchanger of  claim 47 , wherein said heat exchanger is an enthalpy heat exchanger with said sheet material provides for the transfer of moisture between the sets. 
     
     
         51 . The heat exchanger of  claim 50 , wherein said sheet material is paper or cloth. 
     
     
         52 . The heat exchanger of  claim 51 , wherein said heat exchanger includes a plurality of stacked frames, each frame providing a respective one of the sets, with adjacent frames being separated, and each frame includes a plurality of generally parallel walls separating the passages. 
     
     
         53 . The heat exchanger of  claim 52 , wherein sheet materials separate the frames. 
     
     
         54 . The heat exchanger of  claim 53 , wherein each passage has a substantially constant transverse cross-section, with the flow restriction means being a reduction in the cross section. 
     
     
         55 . The frame of  claim 14 , wherein the flow restriction means is a projection that projects into the passages to reduce the transverse cross section thereof. 
     
     
         56 . The frame of  claim 14 , wherein the flow restriction means is a web that varies thickness and that extends across said walls. 
     
     
         57 . The frame of  claim 56 , wherein said frame is moulded from plastics material. 
     
     
         58 . The frame of  claim 57 , wherein said first lengths extend at approximately 90° to said second lengths. 
     
     
         59 . The frame of  claim 58 , wherein the parallel walls are joined by longitudinal end walls so that in transverse cross section the parallel walls and end walls are of a sinusoidal configuration. 
     
     
         60 . The frame of  claim 59 , wherein the flow restriction means aid in maintaining equal dwell time for air passing through the co-extensive portions. 
     
     
         61 . The apparatus of  claim 22 , wherein a filter is located to filter air delivered to said first set of passages. 
     
     
         62 . The apparatus of  claim 61 , wherein said side is provided with a panel displaceable to provide access to said filter. 
     
     
         63 . The apparatus  claim 62 , wherein said housing has a first inlet extending to a first duct, said first duct extending to the inlet openings of said first passages. 
     
     
         64 . The apparatus of  claim 63 , wherein said housing has an outlet through which air is delivered to said room, said outlet communicating with said first fan. 
     
     
         65 . The apparatus of  claim 64 , wherein said body has a further inlet that delivers air to a further duct, said further duct providing air to said second set passages. 
     
     
         66 . The apparatus of  claim 40 , wherein said water delivery means is a spray nozzle assembly. 
     
     
         67 . The installation of  claim 66 , wherein said heat exchanger is a sensible heat exchanger. 
     
     
         68 . The assembly of  claim 67 , wherein said air conditioning apparatus includes a heating means is operable to heat the air delivered to said room from the second set. 
     
     
         69 . The installation of  claim 68 , wherein said heating means includes tubes through which heated water passes. 
     
     
         70 . The installation of  claim 69 , wherein said installation further includes a solar hot water heater that delivers heated water to said heating means. 
     
     
         71 . The installation of  claim 70 , wherein said installation includes a first fan to cause air to pass through said first set and a second fan to cause air to pass through said second set. 
     
     
         72 . The installation of  claim 71 , wherein the fans are driven by electric motors. 
     
     
         73 . The installation of  claim 72 , wherein said installation includes a solar cell assembly that delivers electric current to the fans to drive the fans.