| 摘要 |
<p>1532109 Solar heaters PHILIPS' GLOEILAMPENFABRIEKEN NV 2 Aug 1977 [5 Aug 1976] 32369/77 Heading F4U A solar heater comprises an absorber 4 which is thermally insulated from the surroundings by a cover, the cover consisting of at least one sealed and evacuated transparent tube 1 provided with an arrangement 6 for selectively absorbing or releasing hydrogen in the tube interior whereby radiation losses and the temperature of the absorber 4 may be controlled. As shown, a container having hydrogenpermeable walls is located within the tube 1 and contains an electrical heating element and a metal hydride which releases hydrogen at higher temperatures and absorbs hydrogen at lower temperatures. The tube 1 is arranged directly on an absorber 4 provided with ducts 4a for heat transport fluid, e.g. water. The lower portion 2 of the inner side of the tube is provided with a selective radiation absorbing layer of nickel or copper oxide on a substrate of silver, copper or aluminium, or a non-selective heat-reflective layer of tin-doped indium oxide. In a modification, Fig. 3 (not shown), the metal hydride container is arranged in thermal contact with the absorber 4 and the heating element is omitted.</p> |
