IL29057A - Heat exchanger - Google Patents

Description

R S A T E X C H A G E R D i n f) ' *? Π D This invention relates to a labyrinth-type heat exchanger for effecting transfer of heat from a fluid or fluids flowing at one side of a barrier to another fluid or fluids flowing on the other side of the barrier, which heat exchanger has as many applications as there are uses for heat exchangers generally.

For example, it may serve as a boiler, or an appendage to a boiler, or as a furnace, or as a roof, wall or structural panel of a building or room or the like with inherent ducting and heat exchange, or as a separate accessory where outside air used for make-up in a building may be heated by air being exhausted from that building. It may serve as a wall or structural panel of a building, as aforesaid, its unique characteristics offering great rigidity as well as heat exchange potential.. Further, it may be exploited by use of the accoustical properties inlierent in its design as a labyrinth-type heat exchanger, such properties lending themselves inherently to instances where noise is a serious problem in connection with air or other fluid handling.

Labyrinth heat exchangers provide for acceleration and deceleration of fluid flow due to variations in the area available the course of intercellular flow as fluid is progressed through a flow path. . Too, pulsing velocity changes in fluid flow occur, resulting in expansion or contraction, causing the labyrinth or helical flow to accelerate and decelerate and to change paths whereby turbulence is increased to enhance heat transfer.

Efficient heat exchangers of the prior art have been expensive in manufacture, complicated in design, lacking in flexibility as to fields of use, and limited as to scope of application.

The need for an efficient heat exchanger of simple design having a high rate of heat transfer together with a facility, by virtue of a manifolding feature, to provide a wide range of capacities, has long been felt.

A primary object of the invention is to provide a heat exchanger of modular type design wherewith infinite variations can be approached by the simple expedient of increasing or decreasing the number of modules, or the size of the modules, or the length or configuration of the flow paths.

Another object is to provide a heat exchanger having an extremely high rate of heat transfer resultant from the unique' construction of the fluid flow paths through the structure, which structure has an extremely high strength in its design.

As another feature worthy of particular notice, the exchanger hereof may be used as either a parallel or counterflow type or as a temperature equalizer prior to fluid blending.

According to the present invention there is provided a heat exchanger comprising a cellular panel providing a primary series of interconnected fluid carrying cells defining a plurality of tortuous fluid flow paths disposed in a common plane and a secondary series of interconnected fluid carrying cells defining a plurality of tortuous fluid paths disposed in a common plane in juxtaposed relation adjacent said primary series with the walls between said primary and secondary series constituting a barrier.

- In one of its embodiments, the exchanger has a plurality of the panels arranged in a plurality of planar groups, in manner such that a flow path of one group may be enclosed on all of its planes by other flow paths of its own group or of adjacent groups.

The heat exchanger of the invention offers the advantages of being structurally sound and economically produced so as to allow ready removal and replacement to the almost complete elimination of maintenance costs, all based upon the principle of planned replacement.

The invention will be described further, by way of example, with reference to the accompanying drawings, which illustrate various embodiments of the heat exchanger of the invention, and wherein Fig.l is a fragmentary, partially-exploded view, in perspective, showing a grille or grid upon which the cellular panels incorporated in the heat exchangers of the invention are based; Pig.2 is a fragmentary, partially exploded view, in perspective, showing a form of cellular panel, which may be derived from the grille or grid of Fig.l, such as is embodied in the heat exchangers of the invention; Fig.3 is a fragmentary view, in perspective, of a first embodiment of the heat exchanger of the invention, and wherein the fluid flow paths of the cellular panel thereof are vertically disposed; Fig.4 is a fragmentary view, in perspective, of a second embodiment of the heat exchanger of the invention and wherein Fig.5 is a fragmentary view, in perspective, of a third embodiment of the heat exchanger of the invention and comprising a plurality of the cellular panels arranged in a stacked relationship; and Fig.6 is a fragmentary view, in perspective, of another form of the cellular panel incorporated in the heat exchanger of the invention, the fluid flow paths thereof being vertically disposed.

The heat exchanger of the invention takes the form of one or two or more heat transfer elements in the form. of cellular panels enclosed and/or separated by heat transfer walls or plates and connected, as by suitable inlet headers or inlet line to supply sources of heated and/or cooled fluids, the heat transfer elements further being provided with suitable outlet headers or outlet lines. Such headering means for inlet and outlet purposes, being widely var¾.iable in respect to type, have not been illustrated in the drawings, in order to simplify the same and to restrict the disclosure to the essentials of the invention.

Herefollowing, where the term "fluid" is employed, it will be understood to mean anything that will flow, whether of liquid or gaseous form.

The invention has been entitled a "heat exchanger" for purposes of convenience, the term being used in its classical sense of any device used to transfer heat from a fluid flowing on one side of a barrier to another fluid flowing on the other side of the barrier.

With detailed reference now to the drawings, Fig.l illustrates grille or grid or latticework formed of metal, plaitics, or equivalent material and from which a heat transfer element, in the form of a cellular panel, for incorporation into a heat exchanger of the invention can be dei-ived. The grille or grid comprises a plurality of equi-spaced, parallel, upright longitudinally-extending barlike walls 20 and a plurality of equi-spaced, parallel, upright, transversely-extending barlike walls 30 normal to and intersecting the longitudinal walls 20 thereby to define a plurality of generally square or rectangular or other shaped, non-cojmnunieating, cells or chambers 40, each such cell or chamber being bounded by portions of an adjacent pair of the walls 20 and portions of an adjacent pair of the walls 30.

Such grille or grid or latticework so described may be of the interdigitating type such as are frequently employed in fluorescent light fixtures f;.r diffusion of light.

Fig.2 illustrates a heat transfer element in the form of a cellular panel 10, exemplifying the form of the cellular panel incorporated in the heat exchangers of the invention, and derived from e grille or grid of Fig.l by upsetting or deforming certain portions of the walls 20 and 30 between adjacent ones of the chambers 40 to afford communication between said chambers. A plurality of such communicating chambers define a flow path.

The walls 20 a,nd 30 are upset or deformed, not randomly, but according to a pattern or patterns, so as to provide a plurality of flow paths through the heat transfer element or cellular panel, as will be explained more fully hereinafter.

Portions of the walls 20 and 30 are deformed downwardly from their respective top planar surfaces or are upset upwardly from their respective bottom planar surfaces so as to project normally in the direction of fluid flow and to provide ports communicating between adjacent chambers.

Such upsetting or deforming may be to either side of the particular wall 20 or 30. For example, in the case illustrated in Fig.2, each of the walls 20 is shown as provided with a plurality of equi-spaced tabs 22 which are formed by deforming or bending the respective parts of the wall downwardly from its top planar edge so that the tabs extend outward^ from each side face of the wall in an alternating manner and thereby define a plurality of equi-spaced ports 24 through the respective wall .

Comparably, each of the walls 30 is shown as provided with a plurality of equi-spaced tabs 32 formed by upsetting or bending the wall upwardly from its bottom planar edge so that the tabs extend outwardly from each side face of the wall in an alternating manner and provide a plurality of equi-spaced ports 34 through the respective wall.

The deforming or upsetting of certain portions of the walls 30 inwardly and/or outwardly and/or the deforming or upsetting of certains portions of the walls 20 inwardly and/or outwardly, whereby intercommunication between certain of the cells or chambers 40 is obtained, is carried out throughout the entirety -of the basic grille or grid to achieve the heat exchange element or cellular panel 10, so as to provide a plurality of fluid flow paths therethrough.

The ports 24 and 34 afford communication between adjacent ones of the cells or chambers 40, to provide for fluid flow in up-and-down, zig-zag, tortuous paths, as will be more fully explained hereinafter.

The flow paths thus provided offer the advantage of obtaining substantial turbulence of the fluid or fluids passed therealong.

Pig.3 illustrates a form of heat exchanger comprising the heat transfer element or cellular panel 10 of Pig.2 sandwiched as a core between inboard and outboard heat transfer walls or plates 54.

Suitable headers, (not shown) for serving the usual header functions will, of course, be appropriately embodied into the arrangement to provide fluid inlets to and outlets from the heat exchanger.

In the Fig.3 embodiment, vertical fluid flow paths are achieved, which flow paths are, for the sake of convenience only, referred to as heated and cooled fluid paths since their functions, could, of course, be reversed.

The heated fluid paths are indicated by the arrows A and the cooled fluid paths are indicated b3r the arrows B, with shading being applied only to the heated fluid paths for the purposes of clarity. The paths can be of the parallel flow type or the counterflow type, as desired, counterflow being illustrated in Fig.3.

The paths A and B alternate throughout the width of the heat exchanger, with each flow path being through one of the ports 34, under one of the tabs 32, into one cell or chamber 40, through a port 24, over a tab 22 and into the next adjacent cell or chamber 40 disposed immediately thereabove Qr thercbelow, where the process is repeated.

It is to be noted that when the flow paths are of equal lengths equal pressure drops are maintained from the inlet header to the outlet header, thereby avoiding short circuiting paths which tend to reduce the overall efficiency of heat transfer.

Differing flow path lengths may be utilized in those instances where it might be advantageous to do so, as in a triple, quadruple or larger fluid heat exchange system.

Each flow path pattern, occurs in a zig-zag or checkerboard fashion in two directions, with each cell or chamber 40 having a tab extending in the third direction which is mutually perpendicular to the plan.es formed by the walls 20,30 and parallel with the plates 50,52.

The Fig. embodiment is identical in construction to that shown in Fig.3, except that diagonal hot and cold flow paths C and D respectively are achieved in lieu of vertical flow paths.

It will.. be appreciated that vertical and/or horizontal flow paths or combinations of diagonal, vertical and horizontal flow paths may be Achieved by approximate arrangements of the ports 24.

In Fig.5 there is shown a manifold or sandwich construction comprising an intermediate heat transfer element or cellular panel 110 comparable with the cellula.r panel 10 disposed between a similar upper heat transfer element or cellular panel 210 and a lower heat transfer element or cellular anel 10 the u er lower and upper heat transfer walls or plates 350 and 352 respectively.

The heat transfer elements or cellular panels are stacked in seriatim with the central heat transfer element or panel 110 being enclosed by the lower plate 250 of the upper heat transfer element or panel 210 and by the upper plato 3 of the lower heat transfer clement or panel 310.

The heat transfer elements are also enclosed by side walls or plates, not shown, and the ends will be suitably connected to headers, also not shown, for fluid inlets and outlets.

While only three heat transfer elements or cellular panels have been shown, for purposes of illustration, in Fig.5, the invention is not 'United to just three thereof, and any number of the transfer elements or panels, providing any desired flow path length or arrangement may be employed to meet different installation or heat transfer requirements.

Each of the heat transfer elements or panels 110,210 and 310 comprises spaced, parallel longitudinally-extending bar-like walls intersected by spaced, parallel, transversely extending bar-like walls as with the embodiments of Figs.2 and 3.

By stacking the heat transfer elements, greater capacity of fluid flow and more complete and efficient heat transfer may be obtained. For example, flow path E of the central transfer element or panel 110 is bounded on two sides in its own plane by flow paths F and G, is bounded on its upper side in the next upper horizontal plane by flow path H, and is bounded on its lower side in the next lower horizontal plane by flow path J.

Of course, the relationship between the flow paths in the several planes may be varied. That is, a hot pa.th in the central element may be bounded on its upper and lower sides by hot paths or by cold paths or it may be bounded on ail of its sides by a counter flow path.

Fig.6 shows an alternative form which the cellular panels incorporated in the heat exchanger of the invention may take. The panel 410 illustrated in this figure is comparable with that of Fig.2, save that the tabs have been omitted, whereby the heat transfer element or cellular panel 410 is particularly adapted for fabrication from a suitable plastics material by moulding.

The tabless, plastic element is preferable for use in tho instances whore strength and rigidity are not critical factors and especially where the clement is required to be periodically removed, discarded and replaced (rather than cleaned) in a programme of planned replacement.

Herein, a plurality of cqui-spaced, parallel and upright walls 420 of the heat transfer element 410 arc intersected by a plurality of cqui-spaced, parallel and upright walls 430 to define a plurality of cells or chambers 440.

The walls 420 arc provided along their top edges with a plurality of spaced ports 424 and the walls 430 are provided along their bottom edges with a plurality of spaced ports 434» the ports 424 and 434 opening into the cells or chambers 440.

The fluid flow paths may be cither vertical, horizontal or diagonal as with the Figs. 3,4 and 5 embodiments. In Fig.6, the flow paths K,L and M are vertical.

While the cells or chambers in all of the embodiments have been shown to be of square or rectangular form, it is to be understood that they may be hexagonal or other practical form.

The flow paths need not necessarily be generally overall linear and can comprise any combination of part linear and part zig-zag, not only in one plane or dimension but in two or three planes or dimensions.

Claims (4)

1. - In an heat exchanger for imparting the heat of one fluid to another fluid without commingling the fluids by passing the fluids through sinuous passages within a common structure, the improvement consisting of: a grille a) comprising a plurality of longitudinally-extending 0 walls intersected by a plurality of transversely-extending /¾¾> #0* ( walls defining a plurality of cells, b) opposite cell-enclosing walls each mutually perpendi- oular ξ. o) transversely-extending walls being deformed at their top edges t and certain portion .lt »jfof being deformed at their bottom Cm, ]\ edges for defining portf *n d) the oell-enclosing walls and certain of the deformed portions and certain of the non-deformed portions of certain of the longitudinally and transversely-extending walls cooperantly defining first 1} a multiplicity of spaced primary series of intercommunicating fluid-carrying cells disposed in a common plane, each of the primary series defining a tortuous first fluid-flow path, and second 2) a multiplicity of spaced secondary series of intercommunicating fluid-carrying cells disposed in the same oommon plane, each of the secondary aeries definin a tor e) each of the secondary aeries "being contiguously juxtaposed between an adjacent pair of primary series; and means permitting inflow and outflow of fluids relative to the grille.

2. In the heat exchanger as set forth in Olaim 1, the flow paths of the multiplicity of primary series of fluid-carrying cells extending in a oommon direction and the flow paths of the multiplicity of secondary series of fluid-carrying cells extending in a direction opposite to said common direction. S. In the heat exchanger as set forth in Claim 1, the flow paths of the multiplicity of primary series of fluid-carrying cells and the multiplicity of secondary series of fluid -carrying cells extending in the same direction. 4. In the heat exchanger according to Claim 1, the porting between the fluid -carr ing cells of a primary series providing an undulating zig-zag modified helical fluid path. 5. In a heat exchanger according to Claim 1, the porting being formed by deforming certain portions of certain walla from one edge and by deforming certain other portions of certain other walls from the opposite edge. θ) each of the secondary aeries being contiguously juxtaposed between an adjacent pair of primar aeriea* and means permitting inflow and outflow of fluida relative to the grille* 3» In the heat exchange as set forth in Claim 1, the flow paths of the multiplicity of primary series of fluid-carrying cells extending in a common direction and the flow paths of the multiplicity of secondary series of fluid-carrying cells extending in a direction opposite to said common direction*

3. In the heat exchanger as set forth in Claim 1, the flow paths of the multiplicity of primary series o fluid -carrying cells and the multiplicity of secondar series of fluid-carrying cello extending in the same direction,

4. In the heat exchanger according to Claim 1, the porting between, the fluid -carryin cells of a rlm&iry aeries providing an undulating zig-zag modified, helical fluid path. S* In a heat exch nger accord ing to Claim 1, the porting being formed by deforming certain portions of certain walla from one edge and by deforming certain other portiona of eertain other walls from the opposite edge . - e) each of the secondary series eing contiguously Juxtaposed be een an adjacent pair of primary series; and m ans permitting inflow and outflow of fluida relative to the grill*. 36. In the heat exchanger as set forth in Claim 35, the flow paths of the multiplicity of primary series of fluid-carrying cells extending in a common direction and the flow paths of the multiplicity of secondary series of fluid-carrying cells extending in a direct ion opposite to said oommon dire o ion. 37· In the heat exchanger as set forth in Claim 35, the flow paths of the multiplicity of primary series of fluid-carrying cells and the multiplicity of secondary series of fluid-carrying cells extending in the same direction. 38. In a heat exchanger aooording to Claim 35, the porting between the fluid-carrying cells of a primary series providing an undulating zig-zag modified helioal fluid path. 39. In a heat exchanger according to Claim 35, the porting being formed by deforming oertaln portions of certain walla from one edge and by deforming certain other portions of certain other walls from the opposite edge . ^ό. In a labyrinth-type heat exchanger for imparting the heat of the fluid to another fluid without commingling of the fluids by passing the fluids through sinuous passages within a common structure, the improvement consisting of: a plurality of grilles disposed in stacked relationship in a multiplicity of planes* a) each grille comprising a plurality of longitudinally- extending walls intersected by a plurality of transversely-extending walls defining a plurality of cells, b) a cell-enclosing well disposed between and common to pairs of adjacent grilles f the stack and a oell-enoloslng wall disposed on the opposite outer sides of the stack* each cell-enclosing wall being mutually perpendicular to the longitudinally and transversely extending walls, c) certain portions of certain of the longitudinally and transversely-extending walls being deformed at their top edges and certain portions thereof being deformed at their bottom edges for defining ports, dj the oell-enolosing walls and certain of the deformed portions and certain of the non-deformed portions of oertain of the longitudinally and transversely-extending walls coopsrant defining first 1) a multiplicity of spaced primary series of intercoinmunicating fluid-carrying oells disposed in a common plane, each of the primary sries defining a helical screw-type firgt fluid-flow bourse, - 16 - 2) a multiplicity of spaced secondary aeries of intercommunicating fluid-carrying cells disposed in the same common plane, each of the secondary aeries defining a helical screw-type second fluid-flow course, e) each of the, secondary series being contiguously juxtaposed between an adjacent pair of primary series, f) and eac of the. secondary series of each intermediate grille being juxtaposed adjacent a primary series on each of its sides; and means for permitting inflow and out flow of the. fluid relative to the grilles. 7. In the heat exchanger as set forth in Claim 6, the fluid-flow courses of the multiplicity of' primary series of fluid-carrying cells extending in a common direction and the fluid-flow courses of the multiplicity of secondary series of fluid-carrying cells extending in a direction opposite to the common direction, 8· In the heat exchanger as set forth in Claim 6, the fluid-flow courses of the multiplicity of primary series of fluid-carrying cells and the multiplicity of secondary series of fluid-carrying cells extending in the same direction. 9. In a heat-exchanger according to Claim 6, the portin between the fluid-carrying cells of a primary series providing an undulating z g-zag modified helical fluid-flow course. 10. In a heat exchanger according to Claim 6, the porting being formed by deforming certain portions of cettain walls from one edge and by deforming certain other portions of 16 - 2) a multiplicity of spaced secondary series of intercoinmunieating fluid-carrying cells disposed in the same common plane , eac of the secondary series defining a helical screw-type second fluid -flow course , e) each of the secondary series being con iguously Juxtaposed between an adjacent pair of primary series, f ) and eac of the secondary series of each intermediate grille being juxtaposed adjacent a primary series on each of its sides; and , , , means for permitting inflow and out flow of the fluid relatlTe to the grilles. 7. In the heat exchanger as set forth in Claim 6, the fluid-flow courses of the multiplicity of primary series of fluid-carrying cells extending in a common direction and the fluid-flow courses of the multiplicity of secondary series of fluid -carrying cells extending in a direction opposite to the common direction. 8· la the heat exchanger as set forth in Claim 6, the fluid -flow courses of the multiplicity of primary series of fluid -carrying cells and the multiplicity of s condary series of fluid -carrying cells extending in the same direction. 9. In a he at -exchang r according to Claim 6, the porting between the fluid -carrying cells of a primary series providing an undulating zig-zag modified helical fluid-flow course . 10. In a heat exchanger accordin to Claim 6, the porting being formed by deforming certain portions of certain walls from one edge and by deforming certain other portions of - 2) a multiplicity of spaced secondary series of interoommunioa ing fluid-carrying cells disposed in the* aame common plant, each of the secondary series defining a helical screw-type second fluid-flow oourse, e) each of he aeoondary series toeing contiguously Juxtaposed between an adjacent pair of primary series, f) and each of the secondary series of eaoh intermediate grille bein juxtaposed adjacent a primary series on eaoh of its sides; and means for permitting inflow and outflow of the fluid relative to the grilles. 41. In the heat exchanger as set forth In Claim 40, the fluid-flow courses o the multiplicity of primary series of fluid-carryin cells extending in a eommon direction and the fluid-flow courses of he multiplicity of secondary series of fluid-carrying cells extending in a direction opposite to the coupon direction* 42· In the heat exchanger as set forth in Claim 40, the luid-flow courses of the multiplicity of primary series of fluid-carrying cells and the multiplicity of secondary series of fluid-carrying cells ex ending In the sam direction. 43· m a heat exchanger according to Claim 40, the porting between the fluid-carrying eella of a primary series proriding an undulating zig-zag modified helical fluid-i'lo course. 44· In a heat exchanger according to Claim 40, the porting being formed by deforming certain portions of certain walls