Dehumidification apparatus

Dehumidification apparatus including a cooled core coupled to an external cooling source, at least first and second relatively humid air inlet pathways leading to the cooled core and at least first and second relatively dry air outlet pathways leading from the cooled core, the outlet pathways being in heat exchange propinquity with the inlet pathways whereby relatively humid air in the inlet pathways is precooled upstream of the cooled core and relatively dry air in the outlet pathways is heated downstream of the cooled core, the cooled core defining a multiplicity of mutually adjacent cooling pathways extending therethrough which are each coupled to one of the inlet pathways and to one of the outlet pathways such that air passes through adjacent ones of the mutually adjacent cooling pathways in mutually different directions.

FIELD OF THE INVENTION

The present invention relates to dehumidification generally.

BACKGROUND OF THE INVENTION

Various types of dehumidifiers are known in the art.

SUMMARY OF THE INVENTION

The present invention seeks to provide improved dehumidification. It may be embodied, for example, as part of a dehumidifier, an air conditioner or a drinking water generation system.

There is thus provided in accordance with a preferred embodiment of the present invention dehumidification apparatus including a cooled core coupled to an external cooling source, at least first and second relatively humid air inlet pathways leading to the cooled core and at least first and second relatively dry air outlet pathways leading from the cooled core, the at least first and second relatively dry air outlet pathways being in heat exchange propinquity with the at least first and second relatively humid air inlet pathways whereby relatively humid air in the first and second relatively humid air inlet pathways is precooled upstream of the cooled core and relatively dry air in the first and second relatively dry air outlet pathways is heated downstream of the cooled core, the cooled core defining a multiplicity of mutually adjacent cooling pathways extending therethrough which are each coupled to one of the at least first and second relatively humid air inlet pathways and to one of the at least first and second relatively dry air outlet pathways such that air passes through adjacent ones of the mutually adjacent cooling pathways in mutually different directions.

Preferably, the cooled core is formed of a material having a relatively high thermal conductivity and the at least first and second relatively humid air inlet pathways and the at least first and second relatively dry air outlet pathways are formed of a material having a relatively low thermal conductivity.

In accordance with a preferred embodiment of the present invention the cooled core is formed of core elements along which an air flow passes, the at least first and second relatively humid air inlet pathways and the at least first and second relatively dry air outlet pathways are formed of pathway elements along which the air flow passes, the core elements have a relatively high thermal conductivity in a direction along which the air flow passes and the pathway elements have a relatively low thermal conductivity in a direction along which the air flow passes.

Preferably, the core elements are aligned and sealed with respect to the pathway elements. Additionally or alternatively, the pathway elements include at least one air flow guiding protrusion. Alternatively or additionally, the pathway elements include at least one air flow blockage protrusion.

In accordance with a preferred embodiment of the present invention the at least first and second relatively humid air inlet pathways and the at least first and second relatively dry air outlet pathways are defined by a stack of embossed generally planar elements which are arranged in generally surrounding relationship about the cooled core. Additionally, an air flow between individual pairs of the stack of embossed generally planar elements is initially pre-cooled, then cooled by the core and then heated.

Preferably, the stack of embossed generally planar elements includes alternating first and second generally planar elements. Additionally, air flows between adjacent ones of the alternating first and second generally planar elements are in a generally counter flow mutual heat exchanging relationship.

In accordance with a preferred embodiment of the present invention the generally planar elements are vacuum formed.

Preferably, the generally planar elements include at least one protrusion and at least one corresponding recess. Additionally, the at least one protrusion and at least one corresponding recess include at least one array of protrusions and corresponding recesses.

In accordance with a preferred embodiment of the present invention the at least one array of protrusions is formed with tapered ends. Additionally or alternatively, the at least one array of protrusions includes at least one downwardly inclined protrusion.

Preferably, the at least one downwardly inclined protrusion provides a pathway for drainage of condensate.

There is also provided in accordance with another preferred embodiment of the present invention dehumidification apparatus including a cooled core coupled to an external cooling source, at least first and second relatively humid air inlet pathways leading to the cooled core and at least first and second relatively dry air outlet pathways leading from the cooled core, the cooled core being formed of a material having a relatively high thermal conductivity and the at least first and second relatively humid air inlet pathways and the at least first and second relatively dry air outlet pathways being formed of a material having a relatively low thermal conductivity.

There is further provided in accordance with still another preferred embodiment of the present invention dehumidification apparatus including a cooled core coupled to an external cooling source, at least first and second relatively humid air inlet pathways leading to the cooled core and at least first and second relatively dry air outlet pathways leading from the cooled core, the at least first and second relatively humid air inlet pathways and the at least first and second relatively dry air outlet pathways being defined by a stack of embossed generally planar elements which are arranged in generally surrounding relationship about the core.

There is even further provided in accordance with yet another preferred embodiment of the present invention dehumidification apparatus including a cooled core coupled to an external cooling source, at least first and second relatively humid air inlet pathways leading to the cooled core and at least first and second relatively dry air outlet pathways leading from the cooled core, the cooled core being formed of core elements along which an air flow passes, the at least first and second relatively humid air inlet pathways and the at least first and second relatively dry air outlet pathways being formed of pathway elements along which the air flow passes, the core elements having a relatively high thermal conductivity in a direction along which the air flow passes, and the pathway elements having a relatively low thermal conductivity in a direction along which the air flow passes.

There is still further provided in accordance with yet another preferred embodiment of the present invention dehumidification apparatus including a cooled core coupled to an external cooling source, at least first and second relatively humid air inlet pathways leading to the cooled core and at least first and second relatively dry air outlet pathways leading from the cooled core, an air flow through the apparatus being precooled in the at least first and second relatively humid air inlet pathways leading to the cooled core, then being cooled in the core and then being heated in the at least first and second relatively dry air outlet pathways leading from the cooled core.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

The present invention describes apparatus which produces dehumidification and can be embodied in a number of alternative operational contexts, such as part of a dehumidification apparatus, an air conditioner or a water generation system providing water for drinking or any other use. The apparatus described hereinabove normally requires an air flow of humid air thereto and a concomitant air pressure gradient thereacross. It also requires provision of a coolant fluid, which may be any suitable gas or liquid.

Reference is now made toFIGS. 1A-3B, which are simplified pictorial illustrations of a dehumidification apparatus100constructed and operative in accordance with a preferred embodiment of the present invention. As seen inFIGS. 1A-3B, the dehumidification apparatus100includes a cooled core102coupled to an external cooling source (not shown) via a cooling fluid inlet pipe104and a cooling fluid outlet pipe106. The cooling fluid may be any suitable coolant, such as ammonia or FREON®, which are supplied in a partially liquid phase and change to a gaseous phase in the core102, or a chilled liquid, typically water or alcohol, which remains throughout in a liquid phase.

At least first and second relatively humid air inlet pathways108lead to the cooled core102and at least first and second relatively dry air outlet pathways112extend from the cooled core102.

In accordance with a preferred embodiment of the present invention, there is provided a core-surrounding air flow pre-cooling and post heating assembly (CSAFPCPHA)120wherein the at least first and second relatively dry air outlet pathways112are in heat exchange propinquity with respective ones of the at least first and second relatively humid air inlet pathways108, whereby relatively humid air in the first and second relatively humid air inlet pathways is precooled upstream of the cooled core102and relatively dry air in the first and second relatively dry air outlet pathways is heated downstream of the cooled core102.

It is a particular feature of an embodiment of the present invention that the cooled core102is formed of core elements, such as core plates122, along which an air flow passes, and the at least first and second relatively humid air inlet pathways and the at least first and second relatively dry air outlet pathways are formed of pathway elements, such as embossed generally planar elements124and126, along which an air flow passes, the core elements having a relatively high thermal conductivity in a direction along which the air flow passes and the pathway elements having a relatively low thermal conductivity in a direction along which the air flow passes. It is appreciated that core plates122are aligned with and sealed with respect to corresponding planar elements124and126.

As seen particularly inFIGS. 1A-1C, the dehumidification apparatus100also preferably includes a base subassembly130, which provides a sump for drainage of condensate, end plate subassemblies132and134, end cover plates136and138, a top air flow sealing plate140which preferably restricts inlet air flow to be along the passageways108, a pair of bottom air flow sealing plates142which preferably restrict outlet air flow to be along the passageways112and a pair of side air flow sealing plates144, which separate between respective pairs of inlet and outlet air flow passageways108and112. A circumferential plate148, shown here symbolically, separates between an ambient relatively humid air environment which is maintained at a relatively high pressure and a relatively dry air environment, which is maintained at a relatively low pressure.

Turning now specifically toFIGS. 2A & 2B, which are simplified illustrations of a base subassembly forming an optional part of the dehumidification apparatus ofFIGS. 1A & 1B, it is seen that the base subassembly is typically welded of sheet metal and includes a pair of mutually inclined plates160and162which are joined by a pair of end portions164and166which define legs168. A pair of sump apertures170are preferably formed at opposite ends of the junction of plates160and162and are preferably fitted with respective sump pipes174.

Turning now toFIGS. 3A and 6A&6B, it is noted that these drawings illustrate a heat exchange assembly including a cooling core102and a core-surrounding air flow pre-cooling and post heating assembly (CSAFPCPHA)120particularly suited for use with a gaseous coolant, such as FREON®, and accordingly coolant piping180is preferably provided with a distributor182, which divides a flow of gas into multiple separate flows, each of which passes through a separate gas circulation pathway.

Turning now toFIGS. 3B and 7A&7B, it is noted that these drawings illustrate a heat exchange assembly including a cooling core102and a core-surrounding air flow pre-cooling and post heating assembly (CSAFPCPHA)120particularly suited for use with a liquid coolant, such as chilled water or alcohol, and accordingly coolant piping190is preferably provided without a distributor182.

Reference is now made toFIGS. 4A & 4B, which illustrate end plate132. It is seen that end plate132comprises a generally planar portion202having an array of apertures204arranged to accommodate coolant piping, such as piping180or190, and preferably includes a plurality of bent over edges206and a plurality of double bent over edges208onto which end cover plate136may be sealingly attached.

Reference is now made toFIGS. 5A & 5B, which illustrate end plate134. It is seen that end plate134comprises a generally planar portion222having an array of apertures224arranged to accommodate coolant piping, such as piping180or190, and preferably includes a plurality of bent over edges226and a plurality of double bent over edges228onto which end cover plate138may be attached. It is noted that one of bent over edges226is preferably formed with an aperture230which accommodates cooling fluid inlet pipe104and cooling fluid outlet pipe106.

Reference is now made toFIGS. 8A-12B, which illustrate the structure of the core-surrounding air flow pre-cooling and post heating assembly (CSAFPCPHA). As seen inFIGS. 8A & 8B, the CSAFPCPHA is made up of a stack of two different embossed generally planar elements124and126which are preferably arranged in mutually interdigitated touching relationship with each other about the core102.

The structure and operation of embossed generally planar elements124and126will now be described with specific reference toFIGS. 9A-12B. It is noted that planar elements124and126are preferably formed by conventional vacuum forming techniques from relatively non-conductive flexible material, typically plastic, such as PVC and PET, typically of thickness 0.3 mm.

Turning first to generally planar element124, a first side thereof, designated by reference numeral300, is shown inFIGS. 9A and 9Band a second side thereof, designated by reference numeral302, is shown inFIGS. 10A and 10B. Planar element124preferably has ten side edges, which are designated, clockwise with reference toFIG. 9A, by reference numerals320,321,322,323,324,325,326,327,328and329. Planar element124is formed with a number of protrusions, which extend above the plane, designated by reference numeral330, of planar element124, in the sense ofFIG. 9A, to a height of approximately 3 mm and which will now be described in detail. Due to manufacture of planar elements124and126by vacuum forming, there are recesses which correspond with each of the protrusions.

As seen inFIGS. 9A & 9B, a first side300of planar element124includes an air flow blockage protrusion340, which extends clockwise in the sense ofFIG. 9A, at first narrowly, from a location near the junction of edges320and329, along and slightly spaced from edge320where it becomes wider and then narrows, and narrowly along and spaced from edges321and322. Protrusion340serves to prevent air flow above plane330via edges320,321and322. Planar element124also includes an air flow blockage protrusion342, which extends clockwise in the sense ofFIG. 9A, narrowly, from a location near the junction of edges325and326and along and slightly spaced from edges326,327and328. Protrusion342serves to prevent air flow above plane330via edges326,327and328. Planar element124also includes an air flow blockage protrusion344, which extends along and slightly spaced from edge324. Protrusion344serves to prevent air flow above plane330via edge324.

Planar element124also includes, at first side300, an air flow guiding protrusion346at what is typically an inlet region348above plane330and an air flow guiding protrusion350at what is typically an outlet region352above plane330.

Planar element124also includes, at first side300, an array360of mutually spaced enhanced counter flow heat exchange (ECFHE) protrusions362downstream of inlet region348. Each of mutually spaced protrusions362preferably has a tapered inlet end364and a tapered outlet end366.

Planar element124also includes, at first side300, an array370of mutually spaced enhanced counter flow heat exchange (ECFHE) protrusions372upstream of outlet region352. Each of mutually spaced protrusions372preferably has a tapered inlet end374and a tapered outlet end376.

Planar element124also includes, at first side300, a plurality of mutual inner edge spacing protrusions380preferably arranged at the sides of a generally rectangular cutout382which accommodates core102.

Planar element124also includes, at first side300, a plurality of mutual outer edge spacing protrusions390preferably arranged along edges323and329.

As seen inFIGS. 10A & 10B, second side302of planar element124includes a recess440, which extends counterclockwise in the sense ofFIG. 10A, at first narrowly, from a location near the junction of edges320and329, along and slightly spaced from edge320, where it becomes wider and then narrows, and narrowly along and spaced from edges321and322. Planar element124also includes a recess442, which extends counterclockwise in the sense ofFIG. 10A, narrowly, from a location near the junction of edges325and326and along and slightly spaced from edges326,327and328. Planar element124also includes a recess444, which extends along and slightly spaced from edge324. Recesses440,442and444cooperate with corresponding protrusions on planar element126to provide enhanced registration of the stack of interdigitated planar elements124and126.

Planar element124also includes, at second side302, an array460of mutually spaced enhanced counter flow heat exchange (ECFHE) recesses462downstream of inlet region448. Each of mutually spaced recesses462preferably has a tapered inlet end464and a tapered outlet end466.

Planar element124also includes, at second side302, an array470of mutually spaced enhanced counter flow heat exchange (ECFHE) recesses472upstream of outlet region352. Each of mutually spaced recesses472preferably has a tapered inlet end474and a tapered outlet end476.

Planar element124also includes, at second side302, a plurality of mutual inner edge spacing recesses480preferably arranged at the sides of generally rectangular cutout382which accommodates core102.

Planar element124also includes, at second side302, a plurality of outer edge recesses490preferably arranged along edges323and329.

Turning now to generally planar element126, a first side thereof, designated by reference numeral500, is shown inFIGS. 11A and 11Band a second side thereof, designated by reference numeral502, is shown inFIGS. 12A and 12B. Planar element126preferably has ten side edges, which are designated, counterclockwise with reference toFIG. 11A, by reference numerals520,521,522,523,524,525,526,527,528and529. Planar element126is formed with a number of protrusions, which extend above the plane, designated by reference numeral530, of planar element126, in the sense ofFIG. 11A, to a height of approximately 3 mm and which will now be described in detail. Due to manufacture of planar elements124and126by vacuum forming, there are recesses which correspond with each of the protrusions.

As seen inFIGS. 11A & 11B, first side500of planar element126includes an air flow blockage protrusion540, which extends counterclockwise, in the sense ofFIG. 11A, at first narrowly, from a location near the junction of edges520and529, along and slightly spaced from edge520where it becomes wider and then narrows, and narrowly along and spaced from edges521and522. Protrusion540serves to prevent air flow above plane530via edges520,521and522. Planar element126also includes an air flow blockage protrusion542, which extends counterclockwise, in the sense ofFIG. 11A, narrowly, from a location near the junction of edges525and526and along and slightly spaced from edges526,527and528. Protrusion542serves to prevent air flow above plane530via edges526,527and528. Planar element126also includes an air flow blockage protrusion544, which extends along and slightly spaced from edge524. Protrusion544serves to prevent air flow above plane530via edge524.

Planar element126also includes, at first side500, an air flow guiding protrusion546at what is typically an inlet region548above plane530and an air flow guiding protrusion550at what is typically an outlet region552above plane530.

Planar element126also includes, at first side500, an array560of mutually spaced enhanced counter flow heat exchange (ECFHE) protrusions562downstream of inlet region548. Each of mutually spaced protrusions562preferably has a tapered inlet end564and a tapered outlet end566.

Planar element126also includes at first side500, an array570of mutually spaced enhanced counter flow heat exchange (ECFHE) protrusions572upstream of outlet region552. Each of mutually spaced protrusions572preferably has a tapered inlet end574and a tapered outlet end576.

Planar element126also includes, at first side500, a plurality of mutual inner edge spacing protrusions580preferably arranged at the sides of a generally rectangular cutout582which accommodates core102.

Planar element126also includes, at first side500, a plurality of mutual outer edge spacing protrusions590preferably arranged along edges523and529.

As seen inFIGS. 12A & 12B, second side502of planar element126includes a recess640, which extends clockwise in the sense ofFIG. 12A, at first narrowly, from a location near the junction of edges520and529, along and slightly spaced from edge520where it becomes wider and then narrows, and narrowly along and spaced from edges521and522. Planar element126also includes a recess642, which extends clockwise in the sense ofFIG. 12A, narrowly, from a location near the junction of edges525and526and along and slightly spaced from edges526,527and528. Planar element126also includes a recess644, which extends along and slightly spaced from edge524. Recesses640,642and644cooperate with corresponding protrusions on planar element124to provide enhanced registration of the stack of interdigitated planar elements124and126.

Planar element126also includes, at second side502, an array660of mutually spaced enhanced counter flow heat exchange (ECFHE) recesses662downstream of inlet region548. Each of mutually spaced recesses662preferably has a tapered inlet end664and a tapered outlet end666.

Planar element126also includes, at second side502, an array670of mutually spaced enhanced counter flow heat exchange (ECFHE) recesses672upstream of outlet region552. Each of mutually spaced recesses672preferably has a tapered inlet end674and a tapered outlet end676.

Planar element126also includes, at second side502, a plurality of mutual inner edge spacing recesses680preferably arranged at the sides of generally rectangular cutout582which accommodates core102.

Planar element126also includes, at second side502, a plurality of outer edge recesses690preferably arranged along edges523and529.

Reference is now made toFIG. 13, which is a simplified partially exploded, pictorial illustration of part of the heat exchange assembly ofFIGS. 3A and 3B, showing typical air flows between adjacent embossed generally planar elements and toFIGS. 14A,14B,14C and14D, which are simplified illustrations of air flow through the heat exchange assembly ofFIGS. 3A and 3B, whereFIG. 14Ais a planar view andFIGS. 14B,14C and14D are sectional views taken along respective section lines B-B, C-C and D-D inFIG. 14A.

FIG. 13shows an airflow, designated generally by reference numeral700, between a first side300of a planar element124and a second side502of a planar element126. The second side502of planar element126is not seen inFIG. 13.FIG. 13also shows an airflow, designated generally by reference numeral702, between a first side500of a planar element126and a second side302of a planar element124. The second side302of planar element124is not seen inFIG. 13.

Considering airflow700, it is seen that a relatively planar flow of typically relatively humid air enters at an inlet region348above the plane330of planar element124, and which is bounded by adjacent second side502of planar element126. This flow is guided by one or more protrusions346into engagement with array360of protrusions362on planar element124and corresponding positioned array670of recesses672of planar element126. It is appreciated that the protrusions362partially seat within corresponding recesses672and together define an air flow passage between each recess672and the corresponding protrusion362partially seated therewithin. It is noted that the tapered ends364and366of the protrusions362and the tapered ends674and676of recesses672assist in defining these air flow passages.

Downstream of arrays360, the air flow, which by this stage has been somewhat pre-cooled, as will be described hereinbelow, passes through the core plates122of core102in a generally planar flow, where it is substantially cooled, preferably to below the dew point. Downstream of core plates122of core102, the substantially cooled air flow passes through array370of protrusions372on planar element124and corresponding positioned array660of recesses662on planar element126. It is appreciated that the protrusions372partially seat within corresponding recesses662and together define an air flow passage between each recess662and the corresponding protrusion372partially seated therewithin. It is noted that the tapered ends374and376of the protrusions372and the tapered ends664and666of the recesses662assist in defining these air flow passages.

Downstream of arrays370, the air flows, which have at this stage been somewhat warmed, as will be described hereinbelow, become joined into a relatively planar flow at outlet region352above the plane330of planar element124, and which is bounded by adjacent second side502of planar element126. This flow is guided by one or more protrusions350.

Considering airflow702, it is seen that a relatively planar flow of typically relatively humid air enters at an inlet region548above the plane530of planar element126, and which is bounded by adjacent second side302of planar element124. This flow is guided by one or more protrusions546into engagement with array560of protrusions562on planar element126and corresponding positioned array470of recesses472on planar element124. It is appreciated that the protrusions562partially seat within corresponding recesses472and together define an air flow passage between each recess472and the corresponding protrusion562partially seated therewithin. It is noted that the tapered ends564and566of the protrusions562and the tapered ends474and476of the recesses472assist in defining these air flow passages.

Downstream of arrays560, the air flow, which by this stage has been somewhat pre-cooled, as will be described hereinbelow, passes through the core plates122of core102in a generally planar flow, where it is substantially cooled, preferably to below the dew point. Downstream of core plates122of core102, the substantially cooled air flow passes through array570of protrusions572on planar element126and corresponding positioned array460of recesses462on planar element124. It is appreciated that the protrusions572partially seat within corresponding recesses462and together define an air flow passage between each recess462and the corresponding protrusion572partially seated therewithin. It is noted that the tapered ends574and576of the protrusions572and the tapered ends464and466of the recesses462assist in defining these air flow passages.

Downstream of arrays570, the air flows, which have at this stage been somewhat warmed, as will be described hereinbelow, become joined into a relatively planar flow at outlet region552above the plane530of planar element126, and which is bounded by adjacent second side302of planar element124. This flow is guided by one or more protrusions550.

Referring additionally toFIGS. 14A-14D, it is seen that the air flows700and702between adjacent partially interdigitated planar elements124and126in the stack are in a generally counter flow mutual heat exchanging relationship, notwithstanding that the air flows are not entirely parallel, particularly at their respective inlet and outlet regions. It is an important feature of the invention that the air flows700and702are generally parallel in two dimensions as they pass through the core102and are generally parallel in three dimensions as they pass though the air flow passages defined between the protrusions and recesses of arrays360and570respectively and as they pass though the air flow passages defined between the protrusions and recesses of arrays370and560respectively.

Thus it may be appreciated that enhanced heat exchange is provided between mutually counter airflows in the air flow passages defined between the protrusions and recesses of arrays360and670respectively and as they pass though the air flow passages defined between the protrusions and recesses of arrays570and460respectively, wherein three-dimensional counter flow is provided, and a lesser degree of heat exchange is provided therebetween in the inlet and outlet regions wherein only two-dimensional heat exchange engagement between adjacent planar air flows is provided.

This can be seen graphically from a comparison ofFIGS. 14B and 14C.FIG. 14Bshows a two-dimensional counter flow heat exchange relationship between adjacent generally planar air flows in the core102between adjacent plates122of the core102.

FIG. 14Cshows a three-dimensional counter flow heat exchange relationship between adjacent generally planar air flows along the flow paths defined by arrays360and670.FIG. 14Calso represents the three-dimensional counter flow heat exchange relationship between adjacent generally planar air flows along the flow paths defined by arrays570and460.

It is appreciated that the heat exchange relationship represented inFIG. 14Cis greatly enhanced as compared with that represented inFIG. 14Bby virtue of the fact that nearly each flow shown inFIG. 14Cis surrounded on four sides by a counterflowing flow path, whereas inFIG. 14B, nearly each planar flow is surrounded on two sides by a counterflowing flow path. It is further appreciated that the protrusions and recesses defining the flow paths are downwardly inclined so to enhance ease of draining of condensate therefrom via edges325and525into base subassembly130for drainage and preferably utilization as drinking water.

Realization of the highly efficient heat exchange structure shown inFIG. 14Cis achieved in accordance with a particular feature of the present invention by the partial interdigitization of the protrusions and recesses described hereinabove and visualized inFIG. 14D, which shows the arrangement of these flow paths in a view taken perpendicular to the planes330and530of the respective planar elements124and126.

It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather the scope of the invention includes both combinations and subcombinations of the various features described hereinabove as well as modifications and variations thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not in the prior art.