| 摘要 |
PURPOSE:To increase the efficiency of thermal conversion by a method wherein a water permeable porous material consisting of a water resistant synthetic resin is filled into the entire region of a water flow passage. CONSTITUTION:A solar ray receiving section 2 comprises the zigzag water passage 21 formed by fusion-bonding two sheets of black vinyl chloride films 23 and 24 and the water permeable synthetic resin porous material 22 made of polyurethane resin is filled into the entire region of the water flow passage 21. For the synthetic resin porous material, it is appropriate to use a foamed material or non-woven cloth made of synthetic resin material provided that such material has a proper degree of water permeability. From this point of view, when the foamed material is used, it is appropriate to use one that has a expansion ratio of at least more than 20 or preferably in the order of about 20-60 with the optimum expansion ratio being about 50 magnifications. |
