ABSTRACT:
The intermittent system used CaCl2 and NH3 as absorbent and refrigerant, respectively. The absorbent was mixed with 20% by weight of CaSO4, as cement, and prepared as hard porous granules of 5–10 mm sizes.The double glazed collector/absorber/generator unit used clear PVC and plane glass sheets, with the former as the outer cover. Overall collector plate exposed area was 1.41 m2. A stagnant water evaporative condenser was designed and constructed of re-inforced sandcrete, with steel condenser tubes, and was coupled to the system. The evaporator was a spirally coiled steel tube immersed in a pool of stagnant water. Absorbent cooling during absorption was by natural convection of air over the collector plate and tubes, coupled with sky radiation. All construction, except the collector covers and porous condenser walls, were of steel sheets and tubes.Ambient temperatures during absorption and generation ranged over (25°–35°C). Tests indicated that cooling capacities of the NH3 condensed were around 714 KJ m−2, while effective cooling obtained was equivalent to an ice production of 1 kg m−2, per day.
Solar Energy 12/1985; 35(5-35):447-455. DOI:10.1016/0038-092X(85)90134-3