Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
  • F24S23/00—Arrangements for concentrating solar-rays for solar heat collectors
  • F24S23/70—Arrangements for concentrating solar-rays for solar heat collectors with reflectors
  • F24S23/77—Arrangements for concentrating solar-rays for solar heat collectors with reflectors with flat reflective plates
• • 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
  • F24S10/30—Solar heat collectors using working fluids with means for exchanging heat between two or more working fluids
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
  • F24S70/00—Details of absorbing elements
  • F24S70/60—Details of absorbing elements characterised by the structure or construction
  • F24S70/65—Combinations of two or more absorbing elements
• • 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

• This invention relates to solar energy collectors.
• the problem to which this invention is generally directed relates to the difficulty of collecting solar energy radiation and effecting a transfeTr ' of this to another fluid such as for instance air in an as efficient manner as is possible.
• a solar energy collection arrangement r. solar radiation absorber member or members arranged to extend across a collection area and adapted to have an outer face or faces facing a solar energy source when in a collection position, and a reflective member having a reflective surface which extends across a reflection area which is at least similar in size to the said collection area, and which has a reflective surface providing substantial reflectivity with a diffusing effect, and which is located to be behind the solar radiation absorber member or members when in a collection position and ' the solar absorber member or members being shaped and/or placed one with r'espect to others and each with respect to the reflective surface, and/or including interstices
• the solar radiation absorber member or members and the reflective member are located together within a confining chamber with one side, that is a forward side of the confining chamber, being a material substantially transparent to the selected solar radiation.
• the reflective surface is such that there is a high degree of reflectivity but it is an important feature that this be such as to effect a diffusing or with respect to the sizes of the absorbers some randomness of reflection direction.
• the reflective surface can be from a substantially non-corrosive surface and can be randomly shaped so as to have a number of very small irregularly orientated faces which thereby do not reduce all-up reflectivity to any significant extent but effect a randomness of the direction.
• the efficiency of the solar energy collector made according to this invention has a high efficiency even when the source of the solar radiation, that is typically the sun, is not directly perpendicular to the general collection area plane.
• the solar radiation absorber member or members comprise a plurality of elongate members, each of substantially constant cross-sectional shape along their length and each parallel one with respect to the others and each separated one with respect to those adjacent by a separation gap to allow the said significantproportion of solar radiation to bypass the members and be directed directly onto the reflective surface.
• each of the elongate members is such that their rearward face is a convex shape in at least cross-section and their forward face is of generally convex shape.
• the relationship between the area of the separation gap and that otherwise covered by the absorber member or members is that the area covered by the separation gap is approximately one quarter of the collection area.
• the characteristic of the reflective surface must be such as to cause a general randomness of reflectivity without losing the degree of reflectivity necessary to provide good efficiency.
• a preferred reflective surface comprises an alumium foil which has been first crushed and then substantially straightened to cover the reflective surface leaving however the substantially random reflective character of the surface shape.
• the steps can include passing a fluid along the absorber member or members so as to be generally in contact with at least substan ⁇ tially all of the absorbent surfaces.
• the solar radiation absorber member or members are preferably of black external colour or of any character such as to promote absorption in the manner of a black body.
• FIG 1 is an illustration of the first preferred embodiment shown in cross-section along the lines 1 - 1 of FIG 2,
• FIG 1A shows the preferred disposition of the absorber members in the said preferred embodiment as shown in FIG 1 and their relationship specifically to the reflective surface
• FIG 2 is a plan view of the first preferred embodiment as shown in FIG 1,
• FIG 3 and FIG 4 are side and end views respectively of the first preferred embodiment
• FIG 5 is a perspective view of the preferred embodiment as shown in the preceding FIG 1 to 4 inclusive,
• FIG 6 is a perspective view of a second preferred embodiment - this embodiment incorporating a water heating coil at an upper end of the confining chamber, and 7 ,
• FIG 7 is a graph showing with respect to the first preferred embodiment the incident modifier results illustrating the way in which efficiency is improved when the angle of solar energy is other than at 90 degrees to the collection plane.
• the confining chamber 1 is of rectangular proportions having sides 2 and ends 3.
• a forward direction and a rearward direction which is used for the sake of convenience and is intended to relate to an expected direction of the collector panel 1 when this is in a collection position that is generally with the front face 4 adapted to first receive radiation from the source of solar energy which would normally be the sun and therefore the backface 5 being that furthest away from the source of solar energy.
• a plurality of solar radiation absorber members 6 each of elongate shape and each of constant cross-section along their length and each parallel one with respect to the other and spaced apart from each other by a separation gap 7.
• the members 6 each are shaped so that there are two legs 8 and 9 which are at right angles one with respect to the other each of equal length and each member 6 is arranged so that the apex of the shape 10 is forward ost and the ends of the legs 8 and 9 in each case are rearwardmost. In this way there is a concave shape 11 on the rearward side of each absorber member 6 and a convex shape on the forward side of each absorber member 6.
• the plurality of absorber members 6 are held in collective arrangement by baffles 12 which besides holding the absorber members 6 in their respective alignments also allow a passage 13 between an upper edge of each baffle 12 and the rearward facing portions of each absorber members 6 so that air can be driven therethrough but in such a manner as to promote some turbulence and therefore collecting efficiency as the air passes the respective surfaces.
• each of the absorber members 6 one with respect to the other and each with respect to the reflective surface is specifically as shown in FIG 1A which is shown to scale with respect to the preferred embodiment.
• the reflective surface 14 has been found to be preferably be comprised of aluminium foil which has been first crushed and then straightened to a degree so as to generally leave a planar shape but nonetheless individual portions being very randomly shaped and therefore able to effect in random direction light falling thereon or other solar radiation but effecting a diffusing of this.
• the reflective surface has been extended to the sides 2 and ends 3.
• the forward face of the confining chamber 1 being 4 is comprised of a transparent sheet material such as a high transmittable glass and this is held in convenient manner by resilient packing 15 and edging 16.
• the side ends and rear face 2,3 and 5 of the confining chamber 1 are comprised of a suitable insulating material which can comprise simply of a wood composite material or it can be improved by providing fibre insulation but the preferred embodiment as shown is as described.
• An air inlet 18 and an air outlet 19 are located through the rearward face 5 through which air can be directed for heating.
• the panel as shown is held in a direction so that its forwardmost face 4 is generally at right angles to the direction of the sun from where the energy will be received and of course that angle will be most appropriate for the latitude of the location.
• the external collector surfaces of the absorber members 6 are as black as can be effectively achieved by conventional techniques and in the arrangement described and with a test procedure conducted according to the ASHRAE Standard 93/77 (Methods of testing to determine the thermal performance of solar collectors) the following results were achieved. It was first found that the incident angle modifier rises as the incidence angle increases and this is shown in FIG 7 in which the incidence angle modifier is shown as K ⁇ and the incidence angle is shown 8 so that at an incidence of 30 degrees there is an incidence angle modifier of approximately of 1.15. The latitude of the test was 38 degrees south.
• the collector tilt for this latitude was 44 degrees.
• this illustrates a confining container 20 which has absorber members 21 held together- by baffle plates 22 and in a spaced relationship Zo crushed and then straightened aluminium foil reflective surface material 23.
• a metallic coil 24 spaced above the reflective surface material 23 and having a black external coating thereon so that fluid passing through the inlet 25 and outlet 26 will be subject to an effective heating effect both by reason of direct solar radiation thereon, and by reason of heating from the air previously heated from the absorber members 21.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Sustainable Development (AREA)
• Sustainable Energy (AREA)
• Thermal Sciences (AREA)
• Physics & Mathematics (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Optical Elements Other Than Lenses (AREA)
• Blinds (AREA)
• Photovoltaic Devices (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=3768989

Family Applications (1)

Country Status (3)

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Family Cites Families (4)

• 1982
  • 1982-03-12 EP EP82900771A patent/EP0074364A1/en not_active Withdrawn
  • 1982-03-12 JP JP57500873A patent/JPS58500419A/ja active Pending
  • 1982-03-12 WO PCT/AU1982/000026 patent/WO1982003263A1/en unknown

Non-Patent Citations (1)

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