الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 145 |  |  |
| | | from | 145 | | |
Abstract
Experimental investigations of the hemispherical solar still (HSS) augmentation with various numbers of evacuated tubes (EVT) was performed and evaluated. The current investigation, which is constructed from inexpensive and locally accessible materials, is rigorously tested and augmented with measurement devices to meet its performance requirements. The proposed system contains two hemispherical distillers, one traditional hemispherical solar still, and the other hemispherical solar still integrated with an evacuated tube collector. The two distillers are fabricated from the same materials and insulation. . The modified one contains a hemispherical dome, basin water, and evacuated tubes. The hemispherical dome is fabricated from acrylic instead of glass, due to its simplicity in assortment, the water basin is made from galvanized steel. The basin water’s inner surface was coated with blackened paint to improve absorption and the evacuated tubes were distributed at an inclined angle of 40º on the perimeter of the water basin base and presented in two categories. The modified hemispherical solar still performance was illustrated with two categories of EVT distributions and compared with the traditional HSS design. In the first category, the EVT was distributed on the water basin perimeter in all directions (Dis-ɸ), and in the second category, the EVT was distributed in the south direction (Dis-So). The impact of various water heights (Hw) from 1 to 4 cm was also studied. Results revealed that the integration of EVT had a significant influence on distillate performance. The highest daily production rate at 1 cm water height of HSS-EVT was 5.86 L with an increment of 551%, 316%, 156%, and 91% compared to THSS at NEVT = 16, 8, 4, and 2 tubes, respectively. The productivity increment by 7.2%, when compared EVT distribution (Dis-ɸ) with (Dis-So) effect. The reduction of water level to 1cm increases the yield by about 5.96%, 11.61%, and 18.74% with HW (2, 3, and 4 cm),
respectively. The proposed system peek value of energy and exergy efficiency was 42.29% and 5.57%, with an increment of 47.30% and 124%, respectively, related to the traditional one. The maximum daily production related to the exposed surface area was 6.69 L/m2 at NEVT = 8 tubes. The estimated cost varied between 0.00237, and 0.0101 USD/L.