IL271135A

IL271135A - Device for extraction of water from air and dehumidifying with high energy efficiency and methods for manufacturing thereof

Info

Publication number: IL271135A
Application number: IL271135A
Authority: IL
Inventors: Dulberg Sharon; Kohavi Arye; Eliahu Maier
Original assignee: Dulberg Sharon; Kohavi Arye; Watergen Ltd; Eliahu Maier
Priority date: 2019-12-03
Filing date: 2019-12-03
Publication date: 2020-01-30
Also published as: IL271135B

Description

DEVICE FOR EXTRACTION OF WATER FROM AIR AND DEHUMIDIFYING WITH HIGH ENERGY EFFICIENCY AND METHODS FOR MANUFACTURING THEREOF TECHNICAL FIELD 1. 1. id="p-1"

[001] The present invention relates to the field of heat exchangers. More particularly, the invention relates to a heat exchanger apparatus and manufacture thereof.

BACKGROUND OF THE INVENTION 2. 2. id="p-2"

[002] Extraction of liquid from gas, such as extraction of water from air, is well known and typically involves enforcement of condensation conditions of gas containing liquid vapor by lowering its temperature below the dew point temperature, thereby causing vapor to condensate and liquid is thereby released from the carrying gas. While this method is highly available, one major obstacle for using it, is the high amount of heat energy needed to be evacuated, in form of both latent heat of the vapor and byproduct of cooling large amount of carrying gas. The high energy cost, and the high cost of available systems often render this solution uneconomic. The energy cost for a given amount of extracted water, is an important factor in deciding to choose this solution among others. This description of embodiments of the invention depicts a heat exchanger and a method, each enable reduction in the energy consumption, and enable to reduce both operational and production costs of extraction machines from this type of solution. 3. 3. id="p-3"

[003] Another implementation of the present invention enables to reduce energy cost in processes when heating is required, and cooling back is possible or required. 1 271135/2 SUMMARY OF THE INVENTION 4. 4. id="p-4"

[004] The invention relates to a heat exchanger comprising a fins and tubes heat exchanger and a plates heat exchanger. The fins and tubes heat exchanger comprises a stack of fins, the fins comprising at least one through hole coupled with a penetrating heat exchanging tube. The plates heat exchanger comprises a stack of plates, at least two sets of flow inlets and two sets of flow outlets, at least a portion of the plates each comprising a void and an embossment. Each one of at least a portion of the fins of the fins and tubes heat exchanger is at least partially attached to or encompassed by a corresponding plate of the plates heat exchanger to define a set of a fin and a plate (SFP) and wherein at least one of: (i) an alternating order of differently plates; and (ii) an alternating orientation of plates in the stack, is adapted to enable one or more of (i) a simultaneous counter fluid flow, (ii) cross fluid flow or (iii) semi counter-cross fluid flow above and below the SFP. The assembly of a stack of SFPs with tubes (e.g. heat exchange fluid tubes) defines a heat exchanger of fins and tubes assembled to plates (HEFTAP). . . id="p-5"

[005] In a first aspect, the invention discloses a HEFTAP comprising fins which at least partially overlap the void of the corresponding plate, and at least a portion of a peripheral margin of the fin is attached to at least a portion of a peripheral margin around the void of the plate such that fluid flowing over either side of the plate comes in contact with the fin. 6. 6. id="p-6"

[006] In a second aspect the invention discloses a HEFTAP wherein at least a portion of the fins comprising at least one through fluid aperture allowing fluid to pass from one side of the fin to the other side. 7. 7. id="p-7"

[007] In a third aspect, the invention provides a HEFTAP wherein the plates comprise lateral peripheral protrusions designed to form, when the plate is stacked with another plate, at peripheral locations intended to be sealed, at least one of: 2 271135/2 8. 8. id="p-8"

[008] (i) a gap between the peripheral protrusions and a surface of an adjacent plate facing the peripheral protrusion, being sufficiently narrow to enable applied adhesive to fill the gap; and 9. 9. id="p-9"

[009] (ii) an outer lateral width of the two plates, enabling an applied adhesive to encircle the outer edges of the plates; . . id="p-10"

[0010] and wherein the plate is designed to form a gap, when the plate is stacked with another plate, between the edge of the plate and the edge of the adjacent plate facing the first plate at locations where the gap should remain open, being larger than a gap allowing an applied adhesive to fill or encircle the gap such that the gap remains open; 11. 11. id="p-11"

[0011] In a fourth aspect, the invention provides a HEFTAP wherein the plates comprise lateral peripheral protrusions designed to form, when the plate is stacked with another plate, at peripheral locations intended to be sealed, a gap between the peripheral protrusions and a surface of an adjacent plate facing the peripheral protrusion, being sufficiently narrow to enable the edges of the plates to melt and coalesce upon applying heat; and 12. 12. id="p-12"

[0012] wherein the plate is designed to form a gap, when the plate is stacked with another plate, between the edge of the plate and the edge of the adjacent plate facing the first plate at locations where the gap should remain open, being larger than a gap allowing the edges of the plates to melt and coalesce upon applying heat such that the gap remains open. 13. 13. id="p-13"

[0013] In a further aspect, the invention provides a HEFTAP comprising plates comprising a fluid inlet zone, a first heat exchanging zone comprising channel protrusions, a second heat exchanging zone, a third heat exchanging zone comprising channel protrusions and a fluid outlet zone, at least one of the fluid inlet zone and the fluid outlet zone comprising uniformizing protrusions configured to reduce the amount of non- uniform fluid mass flow between different channel protrusions in at least one of the first 3 271135/2 heat exchanging zone and the third heat exchanging zone and through the second heat exchanging zone. 14. 14. id="p-14"

[0014] In a further aspect, the invention discloses a plate of a heat exchanger as defined in any one of the definitions above. . . id="p-15"

[0015] In a further aspect, the invention discloses a method for selectively sealing gaps between adjacent plates of a plates heat exchanger comprising the steps: obtaining a plates heat exchanger comprising at least one face comprising peripheral edges of plates as defined in the third or fourth aspect; applying adhesive or heat, according to the type of plate of the plate obtained, to at least one of the faces of the plates heat exchanger comprising peripheral locations intended to be selectively sealed; to obtain a selectively sealed plates heat exchanger at least at one face. 16. 16. id="p-16"

[0016] In a further aspect the invention provides a method for manufacturing a heat exchanger comprising the steps of: (a) obtaining plates of a heat exchanger as defined in one of the aspects as defined above and fins as defined the first aspect; (b) optionally placing an end plate comprising through holes for penetrating heat exchange fluid tubes and optionally inserting at least two longitudinal heat exchange fluid tubes or guiding rods through two of said through holes; (c) laying the obtained fin on top of an assembling surface or on the end plate when applicable while inserting the guiding tubes or rods through the through holes when applicable or having through holes of the fin aligned with through holes of the end plate; (d) laying the obtained plate on the fin having the face of the plate which should be in contact with the fin facing the fin having the void of the plate overlapping a portion of the 4 271135/2 fin comprising at least one through hole for heat exchange tubes and when applicable encompassing the tubes or rods erected from the assembling surface; (e) laying another obtained fin over the plate laid in step d having the face of the fin which is supposed to face the next plate facing away from the previously laid plate and having through holes of the fin are aligned with through holes of the previous fin, so that the through hole is being stringed by the guiding tubes or rods through the through, when applicable; (f) repeating steps d and e until a stack of plates coupled to fins of a desired length is obtained; (g) optionally capping the stack with an end plate; (h) inserting remaining longitudinal heat exchange fluid tube(s) through the through holes of the fins if applicable; and (i) optionally blowing the heat exchanging tube(s) to improve heat transfer between a tube and fin-through hole - to obtain a heat exchanger of plates and fins and tubes assembly. 17. 17. id="p-17"

[0017] In a further aspect, the invention provides an apparatus comprising a compressor, a condenser, an expansion valve and an evaporator enabling a refrigerating process wherein the condenser is a fins and tubes heat exchanger of a heat exchanger as defined above, the evaporator is positioned downstream the heat exchanger such that airflow which exits the heat exchanger flows through the evaporator. Alternatively, the evaporator is the aforementioned fins and tubes heat exchanger, the condenser is positioned downstream the heat exchanger and airflow which exits the heat exchanger flows through the condenser.

BRIEF DESCRIPTION OF THE DRAWINGS 271135/2 18. 18. id="p-18"

[0018] The subject matter regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, both as to organization and method of operation, together with objects, features, and advantages thereof, may best be understood by reference to the following detailed description when read with the accompanying drawings in which: 19. 19. id="p-19"

[0019] Fig. 1A-1B are front schematic illustrations of two types of a plate and a fin defining a set of fin and plate (SFP) of a heat exchanger according to the prior art; . . id="p-20"

[0020] Fig. 1C is a front schematic illustration of a pair of the two types of SFPs of a heat exchanger according to the prior art; 21. 21. id="p-21"

[0021] Fig. 1D is an isometric and partially blown view of a heat exchanger, according to the prior art; 22. 22. id="p-22"

[0022] Fig. 1E is an isometric schematic illustration of a SFP of a heat exchanger according to the prior art including illustration of fluid leakages during operation of the heat exchanger. 23. 23. id="p-23"

[0023] Figs. 2A and 2B are front and back schematic illustrations, respectively, of a SFP according to embodiments of the present invention; 24. 24. id="p-24"

[0024] Fig. 3 is a front view of a SFP according to embodiments of the present invention. . . id="p-25"

[0025] Figs. 4A-4F are front view of a fin (Fig. 4A), side view of the fin (Fig 4B), cross section of the fin along line A-A in Fig. 4A (Fig. 4C), isometric view of the fin (Fig 4D), cross section of the fin (Fig. 4E) along line B-B in Fig. 4A and an enlarged partial view the cross section A-A, according to embodiments of the present invention (Fig. 4F). 26. 26. id="p-26"

[0026] Figs. 5A-5E are: an isometric view of a heat exchanger (Fig. 5A); a top view of a partial cross section view through the fins of the heat exchanger along plane A-A in Fig. 5A (Fig. 5B); a side view of possible selective sealing of gaps between plates of the heat exchanger (Fig. 5C); and isometric views of a heat exchanger before and after selectively 6 271135/2 sealing gaps with a sealant (Fig 5D and 5E, respectively) according to embodiments of the present invention. 27. 27. id="p-27"

[0027] Fig. 6 is a flow chart depicting a method for producing a heat exchanger according to embodiments of the invention. 28. 28. id="p-28"

[0028] Fig. 7 is a flow chart depicting a method for producing a heat exchanger according to embodiments of the invention. 29. 29. id="p-29"

[0029] Fig. 8 is a block diagram depicting an apparatus comprising an airflow exiting a heat exchanger having leaks cooling a condenser downstream the heat exchanger according to embodiments of the invention. . . id="p-30"

[0030] It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous elements.

DETAILED DESCRIPTION OF THE PRESENT INVENTION 31. 31. id="p-31"

[0031] In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the present invention. 32. 32. id="p-32"

[0032] The present invention enables the reduction of heat consumption and may be implemented in various types of processes where cooling a fluid is required, followed by reheating at least some of it (i.e. distillation of ethanol from water-ethanol vapor mixture, solvent vapor extraction for air, humidity extraction from air, etc.). Another application of 7 271135/2 present invention relates to processes when heating the fluid is required and cooling it afterward is possible (i.e. milk pasteurization/UHT process, air sterilization by heat, ozone disassembling by heat, etc.) 33. 33. id="p-33"

[0033] For sake of simplicity, the description mostly refers to a dehumidifier or water- from-air extraction apparatus having a heat exchanger comprising heat exchanging fluid tubes which contain a cold refrigerant, and to air as the subject fluid being treated, including air conditioners, air-dryers, dehumidifiers, water-from-air apparatuses etc. 34. 34. id="p-34"

[0034] However, one who is skilled in the art can adapt the apparatus and the method to other usages under the scope of current invention, some mentioned herein, for example: when the tubes contain a cold heat exchanging fluid; when the tubes contain hot heat exchanging fluid; when the subject fluid is different from air etc., The terms "air" and "fluid" as well as "air flow" and "fluid flow" are thus interchangeably used throughout the specification. . . id="p-35"

[0035] The inventors of the present invention have previously disclosed in U.S. Patent Application Publication No. 2014/0261764 a water extracting apparatus, comprising a heat exchanger assembly, designed to allow efficient heat exchange between pre-cooled inlet air and post heated outlet air so that the pre-cooled inlet flow arrives to the second heat exchanger at a lower temperature where it exchanges heat with the coolant. The high heat exchange efficiency is achieved, among other features, due to the structure of the heat exchanger comprising two types of planar heat exchange elements (i.e. plates of a plates heat exchanger), comprising a void (e.g. a cutout defined by internal edges of the plates) and differing only by having two different embossment topographies, which are alternately arranged in a stack. As the cutouts are all aligned with each other, the stack of heat exchange plates defines a plates heat exchanger having a void in its center. The void in the stack of plates heat exchanger encompasses a stack of fins comprising through holes 8 271135/2 coupled to heat exchange tubes, which defines a fins and tubes heat exchanger serving as a cooled (or heated) core of the assembly, along which an air flow may pass. Fins of the fins and tubes heat exchanger are coupled to plates of the surrounding plates heat exchanger such that each fin coupled to a plate forms a set of fin and a plate (SFP). The assembly of a stack of SFPs with tubes (e.g. heat exchange fluid tubes) defines a heat exchanger of fins and tubes assembled to plates (HEFTAP). The HEFTAP may also be viewed as an assembly of a fins and tubes heat exchanger encompassed by plates heat exchanger, such that the fins and tubes heat exchanger is at the core of the assembly.

During the operation of the water extraction apparatus the assembly of the plates heat exchanger surrounding the core fins and tubes heat exchanger produces interleaved, in some embodiments, counter-flows of air over each other, while flowing through the fins of the core in mutually alternant directions. 36. 36. id="p-36"

[0036] Reference is made to Fig. 1A, which is a schematic illustration of a first SFP 110 that includes plate 112 and fin 110B, Fig. 1B, which is a schematic illustration of a second SFP 120 that includes plate 114 and another fin 110B. Fig. 1C and 1D are isometric and partially blown drawing of a pair 130 of SPF and HEFTAP 1000, respectively, wherein the HEFTAP is built from multiple SFPs 110 and 120, and operative according to embodiment of prior art. Each SFP of the HEFTAP is a coupled pair of a plate (112 and 114, respectively) and a pair of fins 110B. Both plates 112 and 114 have a void in the form of a cutout accommodating the fin 110B being coupled to that plate. In the embodiment depicted in Figs. 1C and 1D the two types of plates 112 and 114 are identical except for their embossments being mirror image of each other. The embossment is configured to channel the fluid flow in a designed pathway. The mirror image embossment of plates 112 and 114 and the alternating arrangement of the SFPs 110 and 120 dictates that a fluid such as air flowing into the HEFTAP 1000 is split into two main flows, flow A and flows B. 9 271135/2 Each flow A flows between two SFPs in front of the face of an essentially planar SFP 110 and behind the back face of essentially planar SFP 120. Each flow B flows between two SFPs in front of the face of an essentially planar SFP 120 and behind the back face of next essentially planar SFP 110. Flow A enters the area of SFP 110, between two plates 112 and 114 (plate 114 which enclaves flow A is shown only in Fig. 1D), via fluid inlet zone 110D, then channeled over a first heat exchanging zone 110A, then between two fins 110B, through a second heat exchanging zone corresponding to fin 110B, then between two plates 112 through third heat exchanging zone 110C and then through air outlet zone 110E. Similarly, and in counter direction, air flow B enters the area of SFP 120 between two plates 112 and 114 via air inlet zone 120E, then channeled over first heat exchanging zone 120C, then between two fins through a second heat exchanging zone corresponding to fin 110B, then between two plates through third heat exchanging zone 120A and then through air outlet zone 120D. 37. 37. id="p-37"

[0037] It is noted that the zones in Fig. 1A-1B are depicted as being separated from one another for sake of simplicity, in order to indicate the areas which are distinctly separated.

However it should be appreciated that the spaces between the zones are part of the overlapping boundaries of two adjacent zones. 38. 38. id="p-38"

[0038] Fig. 1C depicts an isometric view of the combined SFPs 110 and 120, of Figs. 1A and 1B placed one in front of the other to emphasize the resulting combined flows. The directed pathway of flows A and B is achieved, intra alia, due to the flow blockage protrusions 118 and 128 on the periphery of the essentially planar SFPs 110 and 120, respectively. As is clearly seen, airflows A and B flow over each other in cross flow scheme a counter flow scheme or a semi counter-cross scheme (the term "semi counter- cross flow" means that the relative direction of two fluid flows is in between being perpendicular to being counter) in three heat exchanging zone pairs: (i) 110C and 120C, 271135/2 (ii) the two fins 110B of 110 and 120 and (iii) 110A and 120A. Those three zone pairs together with the inlets (110D, 120E) and outlets zones (110E, 120D) renders the heat exchange, while heat can be transferred through the plates and fins. 39. 39. id="p-39"

[0039] The passage of airflow A in front of its respective essentially planar SFP 110, the passage of airflow B in front its respective essentially planar SFP 120, and the way airflows A and B interact with each other are seen clearly in Fig. 1D. By way of example, a fluid flow A flowing from the fluid inlet zone 110D toward the second heat exchanging zone 110B exchanges heat in the first heat exchanging zone 110A with a counter, cross fluid flow or semi-cross counter fluid flow B flowing simultaneously on the other side of the plate 110 through the plate's surface, then the fluid flow exchanges heat with the exposed fins in the second heat exchanging zone 110B, then exchanges heat with a counter fluid flow, cross fluid flow or semi-cross counter fluid flow B on the other side of the plate 110 through the plate's surface in the third heat exchanging zone 110C and exits through the fluid outlet zone 110E. 40. 40. id="p-40"

[0040] Heat exchanger end plate 1002 is also depicted (see below). The term “end plate” relates to a mechanical element of the HEFTAP positioned at an end of the stack of SFPs, enabling the adaption and/or fixation of the HEFTAP to its place. 41. 41. id="p-41"

[0041] One implementation of an improved heat exchanging unit for energy-wise efficiently, while forcing external originating heat exchanging fluid through the tubes of the fin and tubes heat exchanger, is to absorb heat from entering fluid (flows A and B), e.g. humid air, both upstream and on the second heat exchanger zone 110B and heating it back downstream the second heat exchanger zone 110B. That results improving in the energetic efficiency of water extraction process. 42. 42. id="p-42"

[0042] Second implementation of an improved heat exchanging unit for energy-wise efficiently, while forcing hot external fluid through the tubes of the fin and tubes heat 11 271135/2 exchanger, is to heat fluids A and B, i.e. milk to be pasteurized both upstream and in the second heat exchanger zone 110B, and cooling it back downstream the second heat exchanger zone 110B. That results in improving in the economic efficiency of pasteurization process. 43. 43. id="p-43"

[0043] This invention may further involve implementing cheap materials such as plastic plates. Furthermore, volume occupation efficiency where for a given volume occupied by the energetic process to be done, with given conditions, provides larger yield with low energy consumption and lower noise level if desired. 44. 44. id="p-44"

[0044] Reference is now made to Fig. 1E. Leakages of fluid which leak through gaps existing between the fin and the plate, as well as gaps between blocking protrusion and the adjacent plate, contribute to reduction in the effectivity of the heat transfer because these leakages a portion of the inlet air does not fully follow the designated heat exchange pathway. For example, a leak denoted herein as "type I" 140 is a portion of the air flow A which arrives from the inlet zone and the first heat exchanging zone, instead of passing over the fin, passes through the gap 142 between the fin and the plate from one side of the plate to the other side, where it merges with a counter fluid flow B and exits the plate through the flow outlet, without substantially flowing over the fin. Another type of leak, denoted herein as "type II" 150, relates to air which instead of entering through the fluid entry zone, enters the plate through gaps between the blocking protrusions and the adjacent plate, merges with the main fluid flow B over the plate and exits the plate through the fluid outlet without effectively exchanging heat according to the designated flow pathway. Air which enters at a location downstream the second heat exchange zone, i.e. downstream the fin, may have no interaction with the fin whatsoever. 45. 45. id="p-45"

[0045] Therefore, the efficiency of the heat exchange thus depends, among other factors, on the degree of alignment of the void in the surrounding plates 112, 114 with the 12 271135/2 corresponding fins 110B and sealing the gap between them to mitigate the deficient heat exchange caused due to the type I leakage. Mitigating the type II leakage is performed by sealing the gaps between the outer edges of blocking protrusions of one plate and the outer edges of the adjacent plate. 46. 46. id="p-46"

[0046] The inventors of the present invention found a way to facilitate the alignment of the void of the plate with the corresponding fin and the sealing of the gap between the fin and the plate by physical attachment of the fin to the plate through an overlap peripheral margin of the fin and a margin surrounding a void in the plate to which the fin is coupled.

In some embodiments the void in the plate is a cutout in the plate. In some embodiments the plate is a combination of at least two sub-plates which are separated from each other and the void is the space between the at least two sub plates. In some embodiments the plate is a combination of at least two sub-plates attached to each other and the void is generated according to the outline of the edges of the sub-plates. 47. 47. id="p-47"

[0047] Reference is now made to Figs. 2A and 2B which are a back and front exploded view drawings of a "set of fin and plate (SFP)" defined as a coupled pair of a plate of a plates heat exchanger and a fin of a fins and tubes heat exchanger according to an embodiment of the present invention. Plate 212 is one plate out of a stack of plates defining a plates heat exchanger, and fin 210B is one fin out of a stack of fins of a fins and tube heat exchanger. Plate 212 comprises fluid inlet and outlet zones 203A and 203B, respectively, a first heat exchanger zone 205A, a second heat exchanger zone 205B comprising a cutout 214 defined by internal edges of the plate and having an area smaller than the area of fin 210B, and a third heat exchanger zone 205C. When stacked in the HEFTAP, the SFP functions in a similar fashion to the SFP depicted in in Fig. 1D but in an improved manner. In some embodiments, the cutout 214 is at the central area of the plate 212, and in some embodiment, the cutout 214 can be off centered. Fin 210B 13 271135/2 comprises at least one tube through hole 218 each through hole 218 adapted to accommodate and be coupled with a penetrating heat exchanging tube (not shown). The term "through hole" refers to a hole that passes from one side of the article to the other side. In some embodiments protruding flanges may extend from the circumference of the through hole. As the cutout 214 has a smaller area than the fin 210B, then when the fin is attached to the plate to overlap with the cutout 214, only a portion 214B of the fin 210B is exposed through the cutout 214 while a peripheral margin 216B of the fin 210B overlaps with a margin 216 surrounding the cutout 214. Consequently, fluid (e.g. air) flowing over either side of the plate 212 comes in direct contact with the fin 210B. The wider the overlapping margin the more effective is the sealing between the fin and the plate and the more robust is the coupling of the two. On the other hand, a wider overlapping margin narrows the area of the exposed fin, which is where the most effective heat transfer occurs.

In some embodiments, the overlapping margin 216B is between 1 mm to 5 mm wide in order to reduce leakages between flows A and B in the overlapping margin of the plate and the fin. In some embodiments, the overlapping margin 216B is at least 0.3 to 10 mm wide. In some embodiments, the overlapping margin 216B is at least 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 or 1.0 mm wide. 48. 48. id="p-48"

[0048] In some embodiments, only a portion of the periphery of the of the fin overlaps with the surface of the plate while other portions closely fit with the edges of the cutout.

In some embodiments, between 50% to 99% of the periphery of the fin is overlapping with the surface of the paired plate when the plate and fin are coupled to each other. In some embodiments at least 60%, 70%, 80%, 90%, 95%, 98% or 99% of the periphery of the fin is overlapping with the surface of the paired plate when the plate and fin are coupled to each other. 14 271135/2 49. 49. id="p-49"

[0049] The cutout 214 accommodates a portion 214B of the fin 210B comprising at least one heat exchanging tube. In the embodiment depicted in Figs. 2A-2B cutout 214 accommodates the entire area of the fin 210B comprising the tube holes 218. In some embodiments, the portion of the fin 214B is slightly elevated from the plane of the peripheral margin 216B so when the fin is attached to the plate, the portion 214B is coplanar with the plate 212. In some embodiments when the portion 214B is elevated it facilitates locating fin 210B properly in the cutout 214. In some embodiments, the margin 216 is slightly elevated from the main plane of the plate (in some embodiments by 0.1mm- 2mm) to facilitate the placement of the fin 210B in the cutout 214. 50. 50. id="p-50"

[0050] In some embodiments, the fin 210B is adhered to the surface of the coupled plate 212. In some embodiments, an adhesive is applied to the overlapping margin 216B of the fin 210B, to the overlapping margin 216 of the plate 212 surrounding the cutout 214 or applied to both. In some embodiments adhesive is applied over the boundary line between the fin 210B and the plate 212 when the fin and plate are attached to each other. 51. 51. id="p-51"

[0051] Plate 212 is embossed to channel a fluid flow from an inlet zone to a first heat exchanging zone over the plate then to a second heat exchanging zone between two fins, then through a third heat exchanging zone over the plate and then through a fluid outlet zone. In some embodiments as explained above, there are two possible mirror images of embossments, such that when the two plates are stacked in an alternating fashion counter flow of fluid above and below the plate is obtained. In some embodiments, the same embossment produces a fluid flow to a different direction due to a different orientation of the plate relative to the longitudinal axis of the stack of plates. 52. 52. id="p-52"

[0052] It is noted that the term “between the heat exchanging zones" relates to a zone inclusive of the plates and fins themselves as heat exchanging takes place on the fins and on the plates as well. 271135/2 53. 53. id="p-53"

[0053] In some embodiments, the plates are made of low heat-conductive material such as plastic and the fins (as well as the tubes) are made of a high heat conductive material such as a metal or metal alloy. In some embodiments, the plates are made of a material

Claims

1. A heat exchanger comprising: a fins and tubes heat exchanger, comprising a stack of fins, the fins comprising at least one through hole coupled with a penetrating heat exchanging tube; a plates heat exchanger comprising a stack of plates, at least two sets of flow inlets and two sets of flow outlets, at least a portion of the plates each comprising a void and an embossment, wherein each one of at least a portion of the fins of the fins and tubes heat exchanger being at least partially attached to a corresponding plate of the plates heat exchanger to define a set of a fin and a plate (SFP) wherein the fin is at least partially overlapping the void of the plate, and at least a portion of a peripheral margin of the fin of the SFP being attached to and overlapping at least 60% of a peripheral margin around the void of the plate of the SFP such that fluid flowing over either side of the plate comes in contact with the fin; and wherein at least one of: (i) an alternating order of differently embossed plates; and (ii) an alternating orientation of plates in the stack, is adapted to enable one or more of (i) a simultaneous counter fluid flow, (ii) cross fluid flow or (iii) semi counter-cross fluid flow above and below the SFP.

2. The heat exchanger according to claim 1 wherein a first portion of the plates each comprising an embossment configured to channel a first fluid flow between adjacent plates from a first inlet zone toward a first heat exchanging zone, then from between adjacent plates toward a second heat exchanging zone, then from between adjacent fins toward a third heat exchanging zone and then to over a first fluid outlet zone; a second portion of the plates each comprising an embossment configured to simultaneously channel a second fluid flow between adjacent plates from over a second inlet zone toward a third heat exchanging zone, then from between adjacent plates toward a second heat exchanging zone, then from between adjacent fins toward a first heat exchanging zone and then to over a second fluid outlet zone.

3. The heat exchanger according to claim 1 wherein a fluid flowing from the fluid inlet zone toward the second heat exchanging zone exchanges heat in the first heat 41271135/2 exchanging zone with a counter fluid flow, cross fluid flow or semi-cross counter fluid flow fluid flowing simultaneously on the other side of the plate through the plate surface, then the fluid flow exchanges heat with the exposed fins in the second heat exchanging zone, then exchanges heat with a counter fluid flow, cross fluid flow or semi-cross counter fluid flow on the other side of the plate through the plate in the third heat exchanging zone and exits through the fluid outlet zone.

4. The heat exchanger according to claim 1 wherein at least one of the plate and the fin of the SFP comprises attaching protrusions disposed in proximity to the void and adapted to press and attach a fin to a peripheral margin of the adjacent plate around a void.

5. The heat exchanger according to claim 1 wherein the voids of the plates are cutouts defined by internal edges of the plates and in case the fins are attached to the plate the cutout is characterized by having an area smaller than the area of the fin.

6. The heat exchanger according to claim 1 wherein at least a portion of the fins further comprising at least one through fluid aperture allowing fluid to pass from one side of the fin to the other side.

7. The heat exchanger according to claim 6 wherein the at least one through fluid aperture enables a sub-flow from the flow flowing over the fin to flow through the through hole and merge with a sub-flow flow flowing behind the fin to the other direction.

8. The heat exchanger according to claim 6 wherein the at least one through fluid aperture is bypassed by a protrusion.

9. The heat exchanger according to any one of claims 6 wherein the at least one fluid aperture is located in an area wherein the differential static pressure between two sides of the fin had the fin lacked the apertures and had an air flow flowing from first inlet to first outlet and had a second airflow flowing from second inlet to second outlet, is less than 30% of the pressure drop between the inlet and the outlet.

10. The heat exchanger according to claim 1 wherein said plates comprising lateral peripheral protrusions designed to form, when the plate is stacked with another plate, one of: (a) at least one of: 42271135/2 i. a gap between the peripheral protrusions and a surface of an adjacent plate facing the peripheral protrusion, being sufficiently narrow to enable applied adhesive to fill the gap; and ii. an outer lateral width of the two plates, enabling an applied adhesive to encircle the outer edges of the plates; at peripheral locations intended to be sealed, and wherein the plate is designed to form a gap, when the plate is stacked with another plate, between the edge of the plate and the edge of the adjacent plate facing the first plate at locations where the gap should remain open, being larger than a gap allowing an applied adhesive to fill or encircle the gap such that the gap remains open; and (b) a gap between the peripheral protrusions and a surface of an adjacent plate facing the peripheral protrusion, being sufficiently narrow to enable the edges of the plates to melt and coalesce upon applying heat; and at peripheral locations intended to be sealed, and wherein the plate is designed to form a gap, when the plate is stacked with another plate, between the edge of the plate and the edge of the adjacent plate facing the first plate at locations where the gap should remain open, being larger than a gap allowing the edges of the plates to melt and coalesce upon applying heat such that the gap remains open.

11. The heat exchanger according to claim 10 wherein the maximal gap at locations intended to be blocked for fluid flow is smaller than the diameter of a drop of the adhesive being formed when dropped on a surface of the plates.

12. The heat exchange according to claim 10 wherein the minimal gap at locations intended to be open for fluid flow is larger than the diameter of a drop of the adhesive being formed when dropped on a surface made of the same material of surface of the plate.

13. The heat exchanger according to claim 1 wherein the plate further comprising a fluid inlet zone, a first heat exchanging zone, a second heat exchanging zone, a third heat exchanging zone and a fluid outlet zone, at least one of the inlet zone and the outlet zone comprising uniformizing protrusions configured to reduce the 43271135/2 amount of non-uniform fluid mass flow between different fluid flow channel protrusions of first heat exchanging zone then through the second heat exchanging zone, then through the third heat exchanging zone and then through the fluid outlet zone.

14. The heat exchanger according to claim 13 wherein the embossment of the uniformizing protrusions in at least one of the fluid inlet and outlet zone comprises at least one of a bent line protrusion, a dot protrusion, unevenly spaced protrusion lines, non-parallel protrusion lines, non-aligned starting points and non-aligned end points.

15. The heat exchanger according to claim 13 wherein embossment of fluid flow channels in at least one of the first and third heat exchanging zones comprises at least one bent line protrusion in proximity to the inlet or outlet zone respectively.

16. The heat exchanger according to claim 1 wherein the plates are made of a material having a thermal conductivity of less than 5 ^^ and the fins are made of a material having a thermal conductivity higher than 50 ^^ .

17. A method for manufacturing a heat exchanger comprising the steps of: a. obtaining plates of a heat exchanger as defined in claim 1 and fins as defined in claim 1; b. optionally placing an end plate comprising through holes for penetrating heat exchange fluid tubes and optionally inserting at least two longitudinal heat exchange fluid tubes or guiding rods through two of said through holes; c. laying the obtained fin on top of an assembling surface or on the end plate when applicable while inserting the guiding tubes or rods through the through holes when applicable or having through holes of the fin aligned with through holes of the end plate; d. laying the obtained plate on the fin having the face of the plate which should be in contact with the fin facing the fin having the void of the plate overlapping a portion of the fin comprising at least one through hole for heat exchange tubes and when 44271135/2 applicable encompassing the tubes or rods erected from the assembling surface; e. laying another obtained fin over the plate laid in step d having the face of the fin which is supposed to face the next plate facing away from the previously laid plate and having through holes of the fin are aligned with through holes of the previous fin, so that the through hole is being stringed by the guiding tubes or rods through the through, when applicable; f. repeating steps d and e until a stack of plates coupled to fins of a desired length is obtained; g. optionally capping the stack with an end plate; h. inserting remaining longitudinal heat exchange fluid tube(s) through the through holes fins if applicable; and i. optionally blowing the heat exchanging tube(s) to improve heat transfer between a tube and fin-through hole to obtain a heat exchanger of plates and fins and tubes assembly.

18. The method according to claim 17 wherein the stacking is performed in a reverse order, beginning first with laying a plate followed by a fin.

19. The method according to claim 17 wherein plates of different embossment are alternately stacked.

20. The method according to claim 17 further comprising selectively sealing gaps at peripheral locations intended to be blocked of at least one face of the heat exchanger by unselectively applying heat or an adhesive to the at least one face of the heat exchanger.