WO2001027550A2

WO2001027550A2 - New heat exchange panels and methods of manufacture

Info

Publication number: WO2001027550A2
Application number: PCT/US2000/028203
Authority: WO
Inventors: Stephan B. Sears
Original assignee: Sears Stephan B
Priority date: 1999-10-12
Filing date: 2000-10-12
Publication date: 2001-04-19
Also published as: WO2001027550A3; AU1198301A

Abstract

A heat exchange panel (1) for transferring heat to or from a liquid moving therethrough, consisting of a panel (1) formed from two planar sheets (2, 3), each sheet having parallel channels at a non-perpendicular angle to provide non-linear pathways for the liquid moving through the panel, and methods for manufacturing the sheets.

Description

01/27550

NEW HEAT EXCHANGE PANELS AND METHODS OF MANUFACTURE

FIELD OF THE INVENTION

The present invention relates to a new, lightweight heat exchange panel for heating liquids and/or heating or cooling air and to methods of manufacturing sheets from lightweight material.

BACKGROUND OF THE INVENTION

The sun radiates the earth with 400 trillion kilowatt hours of solar heat daily. This is 25,000 times more energy than people consume as fuel and electricity. However, instead of deriving the bulk of our fuel and electricity from this daily shower of solar energy, we rely on our diminishing planetary reserves of fossil fuels- petroleum, coal and natural gas. These fuels formed as plants collected solar energy, stored it as chemical energy, then lay inside the earth under high pressures for millions of years. Much of the petroleum has already been burned by humans. The remainder can only last a few more decades at current rates of consumption.

Basing our energy consumption on fossil fuels creates immediate problems. The price of oil has skyrocketed. Third world countries cannot afford oil and have been prevented from achieving a higher standard of living in part by a shortage of energy. Mining fossil fuels is hazardous-deep mining of coal impairs human health, strip mining of coal disfigures the environment and oil spills destroy sea life. Burning fossil fuels causes contamination of the earth's atmosphere. In the United States, 90% of electricity is produced in power stations that bum fossil fuels. These power stations are fraught with difficulties apart from their dependence on expensive fuel supplies. They are enormously inefficient discharging more energy into the environment as waste heat than they convert into electricity. Pollutants discharged from these power plants have harmed the atmosphere and polluted lakes and other natural water resources.

Although nuclear power plants now supply a portion of electricity in the United States, several factors limit the viability of nuclear power. One by-product of nuclear power plants is plutonium, a man-made element 20,000 times more poisonous than cobra venom. Plutonium must be stored for hundreds of thousands of years before humans-can handle it safely. Another factor weighing against nuclear power plants is the phenomenal cost of building them.

Solar heat exchange panels for providing heated water without electricity, for example for heating swimming pools, are known. Such panels include those disclosed in U.S. Patent No. 4,598,450 by Thompson et al. and in U.S. Patent No. 3,934,323 by Ford et al. In these panels, the fluid passages are a series of tubular chambers joined in parallel (see, e.g. Figure 2 of U.S. Patent No. 4,598,450) or parallel chambers formed within a sheet of material (see Figure 2 of U.S. Patent No. 3,934,323). These panels permit water to flow from the source supplying incoming water straight through to the opposite side where heated water flows out. One problem with such panels, is that water flowing linearly in the chambers is a relatively poor conductor of heat such that transfer of heat into the cooler water passing through the chambers to the other side where it is collected is relatively inefficient.

Previous solar panels typically have been formed using materials of sufficient thickness to provide adequate strength to the panel. Such materials include various plastics such as stabilized polypropylene and plastic polymers. However, plastics are poor conductors of heat and thick panel surfaces reduce the efficiency of heat transfer as well as increasing costs of manufacture.

The thermal efficiency of such solar panels is in the range of 1000 Btu/sq ft (per day). The higher the thermal efficiency, the greater the solar energy collection efficiency, which means it will require fewer square feet of solar panels area to heat a selected amount of liquid. (Florida Solar Energy Center, Testing & Operations Division, Thermal Performance Ratings for Pool Panels, Cocoa, Florida, July 6, 1998).

The use of various metals such as copper, aluminum and stainless steel, or combinations of these metals, particularly stainless steel result in higher costs of manufacture for the thicknesses needed to provide sufficient structural support. In one such panel, the Pro Panel"¹¹ manufactured by Professional Solar Products, Camarillo, California, solar energy must travel a significant distance through aluminum plates to reach water contained within, a central copper core. This structure reduces the efficiency of heat transfer.

The challenge in manufacturing solar panels from strong materials such as metals that are fairly expensive, is to produce a cost-effective product. Costs of manufacture increased with increased weight of material, which is required to impart sufficient strength to the final product.

There remains a need for methods of manufacturing panels from sheets of thin, strong material to provide a structure that imparts sufficient strength for multiple uses, yet remains lightweight, to permit manufacture at lowered costs. In particular, there is a need for heat exchange panels that provide optimal heat exchange, are sturdy and simple to manufacture at lowered cost. In addition there remains a need for systems for heating and cooling air efficiently and inexpensively using such heat exchange panels. The availability of such panels, and systems consisting of such panels, will make this pollution free technology available worldwide at lowered cost and preserve resources.

SUMMARY OF THE INVENTION

Accordingly, the present invention provides heat exchange panels for heating liquids and for heating or cooling air, and to the methods for manufacturing and using the heat exchange panels, resulting in lowered costs of manufacture. 01/27550

The heat exchange panels of the invention consists of a panel formed from two joined sheets having a plurality of parallel channels, such that when the sheets are joined to form the panel, the path of liquid through the panel is non-linear. The non-linear path of the liquid traveling through the panel enhances heat exchange to and from the liquid. This construction permits the sheets to be made of strong but relatively thin material to optimize heat exchange and lower manufacturing costs. When the sheets are joined together to form the panel the channels of one sheet intersect and contact the channels of the opposing sheet creating a non-linear path for the liquid. The panel is preferably inserted into two manifolds, each joined to one opposing end of the panel, to carry liquid to and from the panel.

The method of manufacture of the panels of the invention includes forming sheets with a plurality of parallel channels at a non-perpendicular angle from the edges of each sheet, joining the sheets together such that the channels of one sheet intersect and contact the channels of the opposing sheet, creating a non-linear pathway for liquid moving through the intersecting channels of the joined sheets. The manifolds are formed to provide a slit or slot for inserting the ends of the joined sheets of the panel and may have flanges attached to each edge of the slit or slot for securing the manifold to the sheets of the panel.

In a method of manufacture, two revolving, opposing symmetrical cylinders having lengthwise ridges are used to form in a planar sheet a plurality of parallel channels, consisting of symmetrical troughs and crests.

The heat exchange panels of the invention may be used to heat a liquid such as water by using solar energy in contact with the surface of the panel. In addition, the heat exchange panels of the invention may be used to heat and/or cool air in a structure such as a building. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of an assembled heat exchange panel of the invention illustrating the panel formed from the joined sheets and manifolds at each end of the panel.

FIG. 2A-B is a top view of the sheets used to form the panel of the heat exchange panels of the invention showing the top of the upper sheet (2A) and the top of the lower sheet (2B) of the panels.

FIG. 3A-B is diagrammatic depiction of a cross section of the assembled panel of the invention, taken as a sectional view along line 3-3 of FIG. 1, showing the plurality of parallel channels formed in the top and bottom sheets of the panel when the sheets are separate (FIG. 3 A) and when joined (FIG. 3B), FIG. 3B showing the points of contact between the crests of each sheet.

FIG. 4A-D are side views of a manifold of the heat exchange panels of the invention (4A and B); a side view from inside the manifold of FIG. 4A into which the panel of the invention has been inserted (4B); a side view of an alternative embodiment of the manifold (4C); and a side view from inside the manifold of FIG. 4C into which the panel of the invention has been inserted (4D).

FIG. 5A-B are isometric views of a connector and insert for connecting the panels of the invention; 5A shows a connector for inserting into the manifolds of assembled heat exchange panels of the invention; and FIG. 5B is an insert for connecting the assembled heat exchange panels of the invention, by inserting the manifolds of each panel assembly through the holes in each end of the insert.

FIG. 6 is a diagrammatic depiction of the path of liquid traversing the joined sheets of the heat exchange panel of the invention in the exchange panels of the invention viewed from the top 01/27550

and looking down through the panel as a liquid enters from the (o denotes hquid flowing upwards towards the eye of the viewer; ® denotes liquid flowing downwards).

FIG. 7 illustrates a system constructed from four heat exchange panels and manifolds of the invention joined using connectors and inserts.

FIG. 8 A and B is a diagrammatic depiction of a method of manufacture of the sheets of the invention using two revolving, opposing symmetrical cylinders bearing lengthwise rounded ridges. FIG. 8 A depicts a cylinder and FIG. 8B is a depiction of the cross-section of two cylinders having a sheet inserted between the cylinders for manufacture.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a heat exchange panel. The heat exchange panel is lightweight, yet strong, and provides optimal heat transfer to or from a liquid moving through the panel. The panels may be made simply and at economical cost. This improved panel is made using two sheets of material such as metal or plastic, with each sheet being shaped or "corrugated" to impart strength to the panel formed from the sheets and to provide channels for non-linear flow of a liquid traversing the panel. The alignment of the channels when the sheets are joined forces liquid entering the panel through the panel from entry to exit in a non-linear pathway that creates turbulence in the liquid resulting in enhanced heat exchange between the liquid and the outer surface of the panel. The panels of the invention consisting of two joined sheets constructed as described herein form a flattened tube which optimizes strength and heat exchange.

More specifically, when the sheets are joined the channels in each sheet intersect and the crests of each sheet are placed in contact at the points of intersection, such that liquid moving through the channels (troughs) in each sheet of the panel is forced to make repeated abrupt changes in direction, essentially at right angles, creating a "tumbling" motion. This movement optimizes heat exchange as the turbulence of the hquid results in more even temperature 01/27550

distribution throughout the liquid flowing through the panel. Because the "corrugated" construction of the heat exchange panels of the invention permit materials of less thickness to be used, while retaining strength and promoting efficient heat transfer, the heat exchange panels of the invention may be made at lowered costs, without sacrificing efficiency. Heat exchange panels of the invention may be manufactured to provide approximately 1500 - 2000 BTU/sq ft per day at sijTnificantly lower costs than other heat exchange panels presently available.

The present invention also provides a ύiethod of manufaeturing sheets for multiple uses from strong, yet lightweight materials, by constructing multiple symmetrical channels in the sheets which impart strength, resulting in lowered costs of manufacture.

The structure and methods of manufacturing of the invention are clarified by referring to the Figures. As depicted in FIG. 1 and FIG. 2, in a preferred embodiment, the heat exchange panel 1 of the invention consists of two joined corrugated sheets 2 and 3 forming a panel 4 ending in two hollow tubular manifolds 5 and 6 for carrying liquid into and out of the panel 4. The sheets are made of any suitable material, such as metal, alloys or plastic. Preferably, the material is relatively thin. For example, stainless steel, copper or aluminum or mylar sheeting may be used, having a thickness of from 1/1000 to 3/1000 of an inch. As the thickness of materials used to form the sheets increases, the thermal conductance of the sheet decreases. Thus, if thicker materials are used, the thermal efficiency may be decreased accordingly and the costs of manufacture may increase. The sheets may be made in any dimensions of length and width, for example the sheets may be 1 foot wide by 8, 10 or 12 feet long.

The sheets are formed to have parallel channels to create a "corrugated" structure. The channels are formed at a non-perpendicular angle relative to the edges of the sheet as shown in FIG. 1 and FIG.2. This formation is important because when the top sheets 2 and 3 are placed together to form the panel 4, extended rectangular spiralling pathways for liquid are formed within the panel 4. These pathways increase the thermal conductance through the panel and thus enhance heat exchange. The corrugated structure of the sheets of the invention imparts strength to the resulting panel, as well as increasing the surface area available for heat exchange. The construction of the sheets permits sheets to be formed from thin, lightweight yet strong, material. This reduces the costs of manufacture of the final products made from the sheets.

When the top sheet 2 is joined to the bottom sheet 3 to form the panel 4, the top sheet 2 is attached to the top of bottom sheet 3. FIG. 3A and 3B show in cross-section from FIG. 1 the channels in each sheet consisting of troughs 1 and crests 8 of the-channels formed in the top sheet 2 (FIG. 2A) and troughs T arid crests 8' of the channels formed in the bottom sheet 3 (FIG. 2B). The troughs 7 and 7' of each sheet intersect when the sheets are joined to form the panel 4 and the sheets 2 and 3 contact one another where the crests 8 and 8¹ meet (FIG. 3B).

Preferably, as shown in FIG. 3, the crests 8, 8' and troughs 7, T in each sheet are formed to be curved in shape and are symmetrical. The troughs may be of any dimension, but are preferably from 1/8 to 4/8 inch wide, and from 1/32 to 8/32 inch deep. A preferred ratio of dimensions for the troughs is that the depth be one half of the width. The crests are also preferably from 1/8 inch to 4/8 inch in width and from 1/32 to 8/32 inch deep. This construction enhances the strength of the panel that is formed by joining the sheets and its ability to resist pulling apart under pressure of the liquid flowing through the panel.

The corrugated sheets of the heat exchange panels of the invention may be manufactured in a number of ways, by hand or by machine. The sheets 2 and 3 (FIG. 2) are obtained of the desired length and width from a single sheet of material, such as 2/1000 inch of stainless steel (316L stainless steel, Teledyne Rodney Metals, Los Angeles, CA). Each sheet is then subjected to a forming process in which the material is corrugated, e.g. bent, to create multiple, parallel troughs and crests extending at a non-perpendicular angle from the edges of each sheet. The manufacture of the sheets and panel of the invention may be mechanized and/or automated by any of a number of means. In a preferred embodiment, the sheets 2 and 3 are attached at all points of contact between the crests 8 and 8' (FIG. 3). The points of attachment are preferably closely spaced, e.g. from 1/4 to 1 inch apart to further strengthen the panel. In addition to these points of attachment, the sheets are also preferably sealed or bonded continuously along the long edges 9 and 10 (FIG. 1) forming a leak-tight, flat tube structure.

The sheets are attached together by methods using heat or electrical energy, including welding, soldering, brazing and various chemical bonding such as-adhesives, or a combination of these means. If metal is used to form the sheets, and/or for additional security of attachment, the area of welding may be further protected from corrosion by using a water-proof adhesive or bonding material to form a barrier to entry of the liquid around the weld.

Once the two corrugated sheets are joined, the ends 11 and 12 of the panel 4 are inserted into two manifolds 6 and 5 for inflow and outflow of liquid (FIG. 1). The manifolds preferably are formed from a strong material, either the same or different from the material of the sheets. The thickness of the material used to form the manifolds may be of any dimension however the thicker the material, the more expensive it may be to manufacture. In a preferred embodiment the manifold is made from metal 0.01 to 0.03 inches thick and a diameter for the manifold is from 1/2 to 3 inches. The length of the manifold matches the length selected for the ends 11 and 12 of the panel 4, for example one foot. The joined corrugated sheets 2 and 3 making up the panel 4 may be attached to the manifolds 5 and 6 for liquid inflow and outflow using a number of methods.

In one embodiment shown in FIG. 4, a manifold 5 is formed as an incomplete tube where the edges do not meet forming a slit 13 that runs the length of the manifold 5 (FIG. 4A). The width of the slit 13 must be sufficient to permit the insertion of the joined edges of the panel 4 (FIG. 4B). However, the acceptable width of the slit 13 will also depend on the elasticity or "give" of the material used to form the manifold. In an alternative embodiment shown in FIG. 4C, the manifold 5 has flanges 14 and 15 around slit 13. Referring to FIG. 1, to attach the manifolds, the ends 11 and 12 of the joined, corrugated sheets 2 and 3 of the panel 4, are inserted through the slit 13 and between the edges of the slit 13 (FIG. 4 A) or between the flanges 14 and 15 (FIG. 4C) in each manifold 5. Once inside the manifold 5, the ends 11 and 12 of the sheet are sealed in contact with the edges of the manifold 5, for example using a ribbon of adhesive. Alternatively, as shown in FIG. 4D, the channels of the sheets end short of the edges leaving flat portions 16 and 17 and these are folded back to contact the inner walls of the manifold 5. These flat portions 16 and 17 are then attached to the inside walls of the manifold 5, using e.g. using an adhesive and/or by welding, soldering or brazing. The slit 13 in the mamfold 5 may also be cut out from a full tube of material for the manifold and the edges of manifold forming the slit 13 may be compressed to contact the inserted ends of the joined, corrugated sheets 2 and 3 which are then folded back to contact the inside of the manifold 5 and attached as described above. These embodiments of the panel 4 and manifolds 5 and 6 of the invention provides for simplified manufacture of the heat exchange panels of the invention and prevents leakage of liquid from inside the panel 4 to outside the manifolds 5 and 6.

Individual heat exchange panels 4 may be joined to other panels, for example using simple tube connectors 18 as shown in FIG. 5 A to connect the manifolds 5 and 6 of each panel 4. The connectors 18 are inserted inside the opposing ends of each manifold. Alternatively, the connector may be of wider diameter than the manifolds and the manifolds are inserted into the connector 18. In addition, the joined panels may be further supported by placing inserts 19 (FIG. 5B) consisting of two members 20 and 21 having openings 22 and 23 between each assembled panels. As shown in FIG. 5 and FIG. 7, the panels 4 are inserted between the insert members 20 and 21 with the ends of manifolds 5 and 6 inserted into the openings formed by the alignment of openings 22 and 23 in insert members 20 and 21. The insert members are attached, for example using pins or bolts 24 and 25. The inserts are preferably hollow and made of a strong material such as stainless steel, for example 0.01 to 0.03 inches thick. Using such connectors 18 and inserts 19, systems may be assembled consisting of multiple heat exchange panels as shown in FIG. 7. The path of the liquid is shown diagrammatically in FIG. 6 taken as a section from the top sheet 2 depicted in FIG. 2A when joined to the bottom sheet 3 depicted in FIG. 2B. FIG. 6 shows two of multiple simultaneous paths of liquid traversing a panel 4 of the invention. The liquid enters from a manifold into the openings in the panel 4, specifically into the troughs 7 of each sheet 2 and 3. The liquid is typically under pressure from the source and will flow from higher pressure to lower pressure through the panel. From the point of entry as shown in FIG. 6, the liquid travels generally towards the opposite end of the panel 4, making a series of abrupt changes in direction at approximately 90 degree angles. Thus, following .the "upper" pathway, the liquid enters the panel and moves upward at approximately a 90 degree angle into the trough 7 of a channel in the top sheet 2. The liquid then changes direction at approximately a 90 degree angle to flow over the adjacent crest 8 of the bottom sheet 3. The liquid then changes direction at approximately a 90 degree angle to flow downward into the adjacent trough 7 of the bottom sheet 3 and travels along the trough 7 between crests 8 and 8' of the bottom sheet 3 until it once again changes direction at approximately a 90 degree angle to flow upward and over the adjacent crest 8' and down into adjacent trough 7" of the bottom sheet 3. This pattern of flow continues until the water reaches the opposite end of the panel 4 and exits through a manifold 6. It can be seen in FIG. 6 that in the trough 7 or 7 liquid is flowing downward as well as upward in its spiral paths.

In a method of manufacture of the invention, sheets are manufactured using two revolving cylinders as depicted in cross section in FIG. 8. The cylinders 26 and 27 have rounded ridges 28 running the length of the cylinder body, and depressions 29 between each ridge, and may be made of metal or other sturdy material capable of bending the selected sheet material. The cylinders can be of various lengths, for example 24 inches in length. Both cylinders are the same length and have the same number of ridges. The sheet 30, for example a stainless steel sheet, is advanced between the cylinders 26 and 27^ which revolve in opposite directions. The dimensions of the ridges 28 and depressions 29 match the dimensions of the troughs 31 and crests 32 in the final formed sheet so that when the cylinders 26 and 27 are revolving with the sheet 30 between the cylinders, the ridges 28 of cylinder 27 bend the portion of the sheet 30 into the depressions 29 in the cylinder 26 around the ridges 28 of cylinder 26, forming a plurality of channels consisting of troughs 31 and crests 32 in the resulting metal sheet 30. The ridges 28 preferably are continuously rounded to smoothly engage the sheet material at points of contact between the ridges 28 and the sheet 30. The sheet 30 is inserted at an angle so as to permit channels to be formed in the entire length of the sheet 30 within the cylinder length.

In one embodiment, cylinders of 24 inches in length and 2 inches in diameter (across the center of the cylinder from ridge top to ridge top) are used having twelve ridges on each cylinder as seen in Figure 8. The angle between each two adjacent ridges taken from the center of the cylinder is 30 degrees. A sheet 10 feet long by 1 foot wide is inserted from the left at a 3 degree angle taken from the length axis of the cylinder, providing symmetrical troughs and crests of 1/4 inch wide by 1/8 inch deep. Preferably, the diameter of the cylinder and the number of ridges per cylinder are selected so that the sheet material is pulled into the cylinders at a rate that provides sufficient sheet material to permit the full formation of each successive crest or trough in the sheet before the next is started, without stretching of the material.

This method of manufacture produces proper structure of the sheets and final panel, and prevents stretching. Bending material, such as metal sheets, permits much lower manufacturing costs than would be required if the material was stretched, and preserves the integrity of the material. This method of manufacture can be automated, for example by incorporating the revolving cylinders 26 and 27 into an automated system which contains a feeding mechanism for the panel sheets 30. The resulting corrugated sheets may be used for a variety of uses including the heat exchange panels of the invention, containers, machine walls, and other structural items.

At flow rates of from 10 gallon/hour to 120 gallon hour the abrupt right angle turns will create a turning movement or "turbulence" that moves heat through the hquid evenly by convection and increases the conductance of the liquid. Optimal heat exchange occurs when the liquid is at a uniform temperature throughout. The assembled heat exchange panel is preferably coated, e.g. with black color, for example a dull (non-reflective) black paint or a black powder coating to enhance solar absorption. The coating also may contain an ultraviolet inhibitor to prolong useful life of the coating. Suitable coatings are commercially available such as Solar Black® powder coating (Morton International, PowderCoatings, Reading, PA) .

Uses of The Corrugated Sheets of the Invention

The corrugated sheets of the invention may be used to form heat heat exchange panels in various lengths and widths as needed. The ultimate length and width will depend on the strength the panel once the dimensions of the channels, ridges and spacing between the attachments of the sheets are selected. For example, panels of 1 foot wide by 8, 10 or 12 foot long may be made using the methods described herein. Individual panels may be joined using the manifold connectors and inserts described above. In one embodiment an installation unit 33 consisting of four panels 1 foot wide by 10 foot long is constructed using four inserts and six manifold connectors to join four panels 4 (FIG. 7). The panels may be installed at any angle or flat on the desired surface, eg. roof, under the flooring or in the ceiling of a structure.

The liquid for heat exchange is supplied to the heat exchange panels of the invention through a source such as a hose emptying into a manifold of a panels. The hquid is then carried away from the panels through the manifold at the opposite end to the desired location to be used or stored. In one embodiment, solar heat is applied to one surface of the panel and the heat is transferred to a cooler liquid, such as water, flowing through the panel from a manifold located at one end. The warmed liquid exits at the manifold located at the opposite end.

The heat exchange panels can be used to heat liquid, such as water economically and efficiently from solar sources for a variety of uses including heating swimming pools. Other liquids include alcohol and gasoline. The heated liquid can also be stored and/or used to provide radiant heating to a residence or other building. For example, heated water obtained, e.g. from heat exchange panels of the invention on the roof of a structure, is moved into heat exchange panels of the invention placed under the flooring of a structure. Cool air in the structure will tend to sink to the floor and heat contained in the liquid in the panels of the panels of the invention will be transferred into the cooler air contacting the panels. This results in heating of the air inside the structure.

Conversely, if cooling of air inside a structure is desired, the heat exchange panels of the invention are installed in the ceiling of a structure. Liquid that has been cooled, for example by a heat pump, is pumped through the panels located in the ceiling. Warm air in the structure will tend to rise and contact the surface of the panels in the ceiling and heat from the air will be transferred into the cooled liquid, resulting in cooling of the air in the structure.

These systems of heat exchange panels can be incorporated into a single structure to provide radiant heating and cooling as needed, regulated, for example by a thermostat.

As described herein, the heat exchange panels of the invention provide a thermal performance of from 1500 to 2000 BTU/sq ft per day and can sustain normal pressures of water flow throughout the panels. The panels can be made economically because less material may be used because of the strength imparted to the sheets of each panel as a result of the corrugated structure of each sheet.

In addition to heat exchange panels, the corrugated sheets of the invention may be used as structural sheets or walls for a variety of applications including as containers, machine walls and other items.

While several illustrative embodiments of the invention have been shown and described, numerous variations and alternate embodiments will occur to those skilled in the art. Such variations and alternate embodiments are contemplated, and can be made without departing from the spirit and scope of the invention as defined in the appended claims and equivalents thereof. The embodiments are not intended in any way to otherwise limit the scope of the disclosure of the protection granted by Letter Patent granted hereon.

Claims

I claim:

1. A heat exchange panel for transferring heat to or from a liquid travelling therein comprising a panel for caπying liquid therethrough, said panel formed from joined sheets, each sheet comprising a plurahty of parallel channels formed at an angle that is not perpendicular to the edges of said sheet.

2. The panel of claim 1 wherein said ςhannels comprise symmetrical troughs and crests of from 1/8 inch to 4/8 inch wide and from 1/32 to 8/32 inch deep.

3. The panel of claim 1 wherein said channels comprise troughs and crests and the channels of each sheet intersect placing the crests of each sheet in contact when the sheets are joined, forming non-linear paths for hquid traveling through said panel.

4. The panel of claim 3 wherein said path comprises extended spirals from entry to exit of said panel.

5. The panel of claim 1 further comprising two tubular manifolds into which the opposite ends of said panel are inserted for carrying liquid to and from said panel.

6. The panel of claim 6 wherein said manifolds each comprise a slit running lengthwise in said panel for receiving the ends of said panel.

7. The panel of claim 6 wherein each said manifold comprises flanges at the edges of said slit for attaching said manifold to the upper and lower sheets of said panel.

8. The panel of claim 1 wherein said sheets are attached at the points of contact between the top and bottom sheet when joined.

9. The panel of claim 3 wherein said sheets are attached at the points of contact between the crests of the top sheet and the crests of the bottom sheet.

10. The panel of claim 9 wherein said sheets are further sealed continuously along the long sides of the panel.

11. A sheet comprising a plurality of symmetrical parallel channels formed at an angle that is not perpendicular to the edges of said sheet.

12. The sheet of claim 11 wherein said channels comprise troughs and crests of from 1/8 to 4/8 inch in width and from 1/32 to 8/32 inch deep.

13. A method for transferring heat to or from a liquid in a heat exchange panel comprising contacting a heat exchange panel for carrying liquid therethrough with air at a different temperature than said liquid, said panel formed from joined sheets, each sheet comprising a plurality of parallel channels formed at an angle that is not perpendicular to the edges of said sheet, and said channels of each sheet forming non-linear paths for hquid travelling through said panel.

14. The method of claim 13 wherein said liquid is selected from the group consisting of water, gasoline and alcohol.

15. The method of claim 13, wherein said channels comprise symmetrical troughs and crests of from 1/8 to 4/8 inch in width and from 1/32 to 8/32 inch deep.

16. A method of manufacturing a heat exchange panel for transferring heat to or from a liquid passing therethrough comprising constructing a panel for carrying hquid therethrough from at least two planar sheets, each sheet comprising a plurality of parallel channels having troughs and crests, said channels formed at an angle that is not perpendicular to the edges of said sheet, and attaching said sheets to form a panel comprising a plurality of intersecting channels therethrough, such that the crests of each sheet are in contact and such that paths of hquid travelling within said panel are non-linear.

17. The heat exchange panel produced by the method of claim 16.

18. The method of claim 16 further comprising attaching manifolds at the opposing ends of said panel.

19. The method of claim 18 wherein said manifold comprises a tube having a continuous vertical slit extending lengthwise in said manifold for receiving the ends of said panel.

20. The method of claim 19 wherein the ends of said panel are inserted into said slit and folded back to contact the inside of said manifold.

21. The method of claim 19 wherein said manifold further comprises flanges located at the edges of said slit and said flanges contact the top and bottom sheets of said panel when the ends of said panel are inserted into the slit.

22. The method of claim 16 further comprising sealing the sheets at the points of contact between the sheets.

23. The method of claim 16 wherein the sheets of the panel are formed using revolving, opposing, symmetrical cylinders comprising ridges and depressions, said ridges of one cylinder inserting into the depression in the opposing cylinder during operation, said sheets formed by introducing a sheet between said revolving cylinders, such that the ridges of one cylinder bends portions of the sheet in contact with said ridges into the depressions and over the ridges of the opposing cylinder forming symmetrical crests and troughs in said sheet.

24. The method of claim 23 wherein each successive crest or trough in the sheet is fully formed between the depression of one cylinder and the ridge of another cylinder before the next to prevent stretching of the material during manufacture.

25. A system for heating ambient air comprising passing a warm liquid through the heat exchange panel of claim 1 such that heat from the hquid in the panel is transferred into cooler ambient air contacting the surface of said heat exchange panels to warm the ambient air.

26. A system for cooling ambient air comprising passing cooled liquid through the heat exchange panel of claim 1 such that heat from warmer ambient air contacting the surface of the heat exchange panel is transfeπed into the cooled hquid to cool the ambient air.

27. An installation unit comprising at least two heat exchange panels for transterririg heat to or from a liquid travelling therein comprising at least two heat exchange panels for carrying liquid therethrough, each said panel formed from joined sheets, each sheet comprising a plurality of parallel channels formed at an angle that is not perpendicular to the edges of said sheet.

28. The installation unit of claim 27 further comprising a manifold at_. the end of each said panel for carrying the liquid to and from the panel.

29. The installation unit of claim 27 wherein said channels comprise crests and troughs of from of from 1/8 to 4/8 inch in width and from 1/32 to 8/32 inch deep.

30. A manifold for attaching to a heat exchange panel to carry liquid into or out of said heat exchange panel comprising a slit running lengthwise through said manifold for receiving the ends of said heat exchange panel.

31. A method of manufacturing a planar sheet having improved strength, comprising forming a sheet having parallel channels therein, using revolving, opposing cylinders comprising ridges and depressions between said ridges, said ridges of one cylinder inserting into the depression in the opposing cylinder during operation, said sheets formed by introducing a planar sheet at an angle between said revolving cylinders, such that the ridges of one cylinder press portions of the sheet in contact with said ridges into the depressions and over the ridges of the opposing cylinder forming channels consisting of symmetrical crests and troughs in said sheet.

32. The method of claim 31 wherein each successive crest or trough in the sheet is fully formed between the depression of one cylinder and the ridge of another cylinder before the next to prevent stretching of the material during manufacture.

33. The method of claim 31 wherein said channels in the sheet comprise symmetrical troughs and crests of from 1/8 to 4/8 inch in width and from 1/32 to 8/32 inch deep.