Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
  • F24S10/00—Solar heat collectors using working fluids
  • F24S10/50—Solar heat collectors using working fluids the working fluids being conveyed between plates
  • F24S10/503—Solar heat collectors using working fluids the working fluids being conveyed between plates having conduits formed by paired plates, only one of which is plane
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
  • F24S10/00—Solar heat collectors using working fluids
  • F24S10/50—Solar heat collectors using working fluids the working fluids being conveyed between plates
  • F24S10/504—Solar heat collectors using working fluids the working fluids being conveyed between plates having conduits formed by paired non-plane plates
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
  • F24S25/00—Arrangement of stationary mountings or supports for solar heat collector modules
  • F24S25/60—Fixation means, e.g. fasteners, specially adapted for supporting solar heat collector modules
  • F24S2025/601—Fixation means, e.g. fasteners, specially adapted for supporting solar heat collector modules by bonding, e.g. by using adhesives
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E10/00—Energy generation through renewable energy sources
  • Y02E10/40—Solar thermal energy, e.g. solar towers
  • Y02E10/44—Heat exchange systems

Definitions

• the present invention relates to an absorber for a thermal collector of a solar installation having an absorber wing for light and heat conversion and a pipe system for a heat transfer medium.
• Absorbers are components of solar installations
• Solar installations principally comprise a solar receiving surface, generally referred to as a collector, the solar loop, and the heat accumulator.
• the collectors are typically mounted on the roof of a house and convert the incident solar radiation into heat.
• Pipelines in which a heat transfer medium, such as a water-glycol mixture, is pumped in a loop, connect the collector to the heat accumulator.
• the pumps are automatically switched into the solar loop via a controller when a temperature sensor signals that the temperature at the collector is higher than that in the heat accumulator.
• the heat of the heat transfer agent is dissipated to the accumulator water in the heat accumulator.
• thermal collectors are used in particular. These are collectors which absorb the incident solar radiation and convert it directly into heat.
• the main component of every thermal collector is the absorber.
• This is a metallic, dark-colored plate which is also partially made of plastic. Since the solar radiation is not transmitted by the absorber and is also hardly reflected, it is largely converted into heat which drains off via the pipe system connected to the absorber.
• the heat transfer agent is located in the pipe system.
• the absorber, with the associated pipe system is located in a weatherproof housing having a glass cover. The air layer enclosed by the glass cover of the housing and the absorber is used as a transparent thermal insulation in the direction of the incident solar radiation. An insulating layer attached below the absorber prevents heat losses via the housing floor.
• the pipe system positioned below the absorber plate is typically made of a meandering, pressure-resistant copper pipe, which is connected at each end to a collection line in order to connect multiple collectors to one another.
• the heat transfer between the absorber plate and the absorber pipe occurs via a linear weld seam between the top of the absorber pipe and the absorber plate.
• the heat transfer via the linear weld seam is not optimal.
• Solvis GmbH has developed a wide soldered connection between the absorber plate and the absorber pipe that is to cause improved heat transfer.
• the soldered connection extends over a graduated circle on the top of the absorber pipe; the soldered connection is produced by filling up the gusset between the pipe mantle and the bottom of the absorber with solder.
• the present invention is based on the object of providing an absorber with an improved heat transmission between the absorber wing, in particular in form of an absorber metal sheet, and the pipe system having reduced manufacturing costs. Furthermore, the present invention is based on the object of suggesting a method for manufacturing the improved absorber.
• this object is achieved in an absorber of the type cited at the beginning, in which the pipe system ( 23 ) is positioned between two metal sheets lying one on top of another that form the absorber wing, the shape of the pipe system being introduced into at least one of the metal sheets and the metal sheets being bonded to one another.
• the shape of the pipe system is introduced into at least one, preferably both metal sheets of the absorber wing, a significantly larger transfer area is available for the incident heat.
• the metal sheets are preferably bonded to one another using an adhesive and additionally in a formfitting or stuff fitting way.
• the joining of the metal sheets through an adhesive significantly reduces the manufacturing costs, since soldering or welding work for manufacturing the absorber may be completely dispensed with.
• the joining of the sheets by an adhesive not only results in a significant cost reduction, but rather additionally improves the dimensional accuracy of the solar collector while simultaneously reducing the reject rate.
• the energy use is significantly reduced in gluing in relation to the current bonding technologies.
• An adhesive from the group of silicone, epoxide, or phenol resin adhesives is preferably used as the adhesive.
• Thermosetting adhesives based on modified epoxide resins particularly have a high long-term resistance to changing temperatures. Furthermore, these adhesives have favorable processing conditions and strength and resistance properties for metal/metal bonds.
• Vaporization of the heat transfer medium is particularly connected to the standstill of the normal loop. This results in elevated corrosion or oxidation on the interior walls of the pipe system if the typical water-glycol mixture is used in particular.
• the metal sheets are provided at least in the region forming the inner surfaces of the pipe system with a coating that inhibits corrosion and/or oxidation.
• the metal sheets are preferably coated completely and on both sides.
• Aluminum sheets are preferably anodized, while sheet steel is particularly provided with a copper or plastic coating. The coating ensures the desired longevity of the solar collectors.
• a roll bond method for manufacturing evaporator plates is known from a brochure of Showa Aluminum Corporation, Osaka, Japan 1993, in which metal sheets lying one on top of another are welded to one another through hot rolling and finally cold rolled to the final thickness.
• the separating agent of the channel regions left out of the welding, which is applied in the screen printing method, is blown out using compressed air before the metal sheets are divided into the individual evaporator plates.
• This method has the disadvantage of the metal sheet thickness change during hot rolling and in the subsequent cold rolling step, since this results directly in corresponding metal sheet length changes. Problems result from this which result in a high reject rate in the following work steps.
• the evaporators must be manufactured from pure aluminum (Al 99.5) in order to allow the introduction of the channels.
• the absorber according to the present invention does not, however, necessarily have to be made of pure aluminum and nonetheless may be manufactured easily in a large piece count.
• a method for mass production of absorbers with a low reject rate is to be suggested that requires little energy and opens up a large design freedom in regard to the design of the pipe system.
• the metal sheets forming the absorber preferably are bonded to one another using an adhesive.
• an adhesive In particular, one-component or two-component adhesives are used, which are resistant to the heat transfer medium and maintain their adhesive properties at least in the temperature range between ⁇ 30° C. and +200° C.
• the adhesive is not first applied after the shaping of the pipe system, but rather already to the starting material of the absorber, which is particularly strip-shaped. Strips coated in this way may be wound up like uncoated strips into a coil without sticking to one another if it is a temperature-dependent hot melt adhesive. The adhesive effect only sets in after heating to a specific temperature.
• the joining of the metal sheets through an adhesive allows the use of metal sheets having the final thickness and final strength, which has advantageous effects on the dimensional accuracy of the absorber while simultaneously reducing the reject rate.
• the energy use is significantly reduced in gluing in relation to typical bonding technologies, such as soldering or welding.
• the adhesive may be rolled on using rollers or spread on using a tool similar to a doctor blade or spatula.
• the adhesive may also be sprayed on in lines, the quantity being metered in such way that no excess adhesive penetrates into the pipe system after the joining of the metal sheets to be glued.
• Suitable aluminum alloys are, for example, the aluminum wrought alloys cited in the following:
• At least the areas of the metal sheets to be glued are subjected to a surface treatment.
• a surface treatment is recommended, which is generated through anodic oxidation of the aluminum sheet.
• a copper or plastic coating may be applied as a corrosion protection.
• further mechanical and/or thermal surface treatments may be performed on the areas to be glued. Mechanical surface treatments (e.g., brushing) remove contamination and roughen the surface, which may have advantageous effects on the strength of the adhesive bond for specific adhesives.
• the thermal surface treatment degreases the surface.
• the joined metal sheets which are cut to absorber size, are additionally bonded to one another.
• This additional bonding fixes the metal sheets until reaching a minimum hardness of the adhesive and unloads the adhesive bond during operation of the collector at high temperatures of the heat transfer medium.
• formfitting bonds active in the absorber plane are generated at multiple locations distributed uniformly on the absorber area using clinching (toxing), which maintain the fixing of the metal sheets required for the adhesive curing and the stabilization of the absorber under all operating conditions.
• the absorbers fixed in this way may leave the press for the joining procedure again immediately and, if necessary, pass through a curing furnace or cure to the required adhesive final strength under normal ambient conditions.
• the metal sheets mechanically fixed in this way may be additionally pressed and/or heated on one another.
• the plates are laid on one another with elastic intermediate layers to form a stack in order to then cure for the required time under the pressure of a press and/or the simultaneous effect of temperature.
• any necessary post-processing follows, such as stamping, bending, flanging, and lacquering.
• a production line for manufacturing an absorber according to the present invention is illustrated in a side view and a top view in FIGS. 1 a , 1 b .
• FIG. 2 shows a schematic section through a collector having absorbers according to the present invention:
• the exemplary embodiment shows a two-train production line in which two metal sheets 1 a , 1 b are processed in parallel.
• the strip-shaped metal sheets 1 a , 1 b which are each uncoiled from a coil 2 a , 2 b , are, after straightening in a roller straightening machine 3 a , 3 b , fed to embossing stations 4 a , 4 b , which introduce the shape for the pipe system through embossing in both metal sheets.
• embossing stations 4 a , 4 b may be dispensed with; in this case, a flat metal sheet is joined to an embossed metal sheet.
• the adhesive application is subsequently performed in both trains using a roller 5 a , 5 b positioned above the line shape in each case. Only after the adhesive is rolled on are the strip-shaped metal sheets 1 a , 1 b cut to the size of the absorber 8 to be manufactured using shears 6 a , 6 b in cutting stations 7 a , 7 b.
• the metal sheets 1 a , 1 b manufactured in the two parallel manufacturing trains and cut to the size of the absorbers, are joined in a compression mold 9 and fixed in their position to one another using clinching (toxing) in a formfitting bond 12 active in the metal sheet plane on at least two locations 11 a , 11 b.
• the absorbers thus fixed leave the compression mold 9 again immediately and reach a curing station 13 in which they cure under the pressure of a press 14 and the simultaneous effect of temperature in batches up to the required adhesive final strength.
• Elastic intermediate layers 15 are located between the curing absorbers 8 , which prevent damage of the absorber pipes embossed on both sides in the curing station 13 . If the capacity of the curing station 13 may not absorb all absorbers 8 which may be manufactured from the two coils 2 a , 2 b , multiple curing stations may be provided to ensure a continuous production flow.
• the transport of the metal sheets 1 a , 1 b between the cutting stations 7 a , 7 b , the compression mold 9 , and the curing station 13 is advantageously performed automatically, for example, using conveyor means and clocked gripping and lifting devices, which are not shown in the figures for reasons of clarity.
• the flat collector identified as a whole with 16 , comprises a weatherproof housing 17 having a glass cover 18 , through which the solar radiation 19 is incident on the surface 21 of the absorber 22 .
• the preferably dark-colored surface 21 largely converts the incident solar radiation 19 into heat, which is dissipated via the pipe system 23 integrated into the absorber 22 , of which only two absorber pipes are shown in cross-section.
• the shape of the absorber pipes is introduced through cold shaping into the metal sheets, which are bonded to one another via an adhesive layer 25 .
• the heat transfer medium, a frostproof water-glycol mixture circulates in the absorber pipes.
• An insulation layer 24 positioned below the absorber prevents heat losses via the floor of the housing 17 , while the air layer enclosed by the glass cover 18 in the absorber 22 acts as a radiation-transparent thermal insulation on the top of the absorber.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Thermal Sciences (AREA)
• General Engineering & Computer Science (AREA)
• Sustainable Energy (AREA)
• Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Life Sciences & Earth Sciences (AREA)
• Sustainable Development (AREA)
• Laminated Bodies (AREA)
• Rigid Pipes And Flexible Pipes (AREA)
• Adhesives Or Adhesive Processes (AREA)
• Chemical And Physical Treatments For Wood And The Like (AREA)
• Solid-Sorbent Or Filter-Aiding Compositions (AREA)
• Engine Equipment That Uses Special Cycles (AREA)
• Photovoltaic Devices (AREA)
• Treating Waste Gases (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=32891753

Family Applications (1)

Country Status (10)

Cited By (2)

Families Citing this family (8)

Citations (25)

Family Cites Families (6)

• 2003
  • 2003-02-19 DE DE10306930A patent/DE10306930B3/de not_active Expired - Fee Related
• 2004
  • 2004-01-22 PT PT04704203T patent/PT1606565E/pt unknown
  • 2004-01-22 ES ES04704203T patent/ES2278299T3/es not_active Expired - Lifetime
  • 2004-01-22 EP EP04704203A patent/EP1606565B1/de not_active Expired - Lifetime
  • 2004-01-22 US US10/545,431 patent/US20060137679A1/en not_active Abandoned
  • 2004-01-22 WO PCT/EP2004/000474 patent/WO2004074749A1/de active IP Right Grant
  • 2004-01-22 AT AT04704203T patent/ATE348988T1/de not_active IP Right Cessation
  • 2004-01-22 DE DE502004002374T patent/DE502004002374D1/de not_active Expired - Fee Related
  • 2004-01-22 AU AU2004213524A patent/AU2004213524B2/en not_active Expired - Fee Related
  • 2004-01-22 DK DK04704203T patent/DK1606565T3/da active
  • 2004-01-22 CA CA002513822A patent/CA2513822A1/en not_active Abandoned

Patent Citations (25)

Also Published As

Similar Documents

Legal Events