Modeling The performance Of Solar Stills Of The City Of Tripoli

Abstract

 The focus of this study is on the possibility of simulation on operating a Solar Still under different climatic conditions in Tripoli city-Libya, which represent the four seasons of the year, to obtain high-level production of distilled water according to the climatic conditions and design values of study. The geographical location and climatic conditions play major role in improving the performance of the Solar Still, thermal efficiency, and production capacity. In addition to the engineering design, the internal structure of the material, which falls under the study of Materials Science. In this paper, an analytical study is presented on the extent radiation conditions, ambient temperature, and wind speed affect the performance of the Solar Still. The study includes a model to solve three differential equations of the glass cover, the basin water and the basin liner for a conventional Solar Still based on the energy balances using Runge Kutta four, considering the effect of ambient temperature and solar radiation based on the ASHRAE Model. The results were obtained using a mathematical model developed using Fortran 95 programming language for the main simulation of heat and mass transfer in the solar still based on a presentation presented in the form of graphs, patterns, and tables that illustrate the change in performance factors such as the temperature of the glass cover, the basin water, the basin liner, thermal efficiency, and hourly and daily productivity under different ambient conditions of ambient temperature and solar radiation. The results show that the highest hourly thermal efficiencies were achieved in the four months of January, April, July, and October: 44%, 49.7%, 69.5%, and 47.6%, respectively. Likewise, the productivity of the conventional distillation device was 0.537 L/m²/h, 1.292 L/m²/h, 1.303 L/m²/h, and 0.935 L/m²/h as the maximum values during mid-day for the different months of January, April, July, and October, respectively. However, the cumulative productivity from 8:00 a.m. to 20:00 p.m. in the months of January, April, July, and October were respectively 3.042 L/m²/day, 8.621 L/m²/day, 8.945 L/m²/day, and 5.664 L/m²/day. It is also noted from the results that the highest temperatures of the basin water were respectively 48.23 C^o, 67.776 C^o, 71.032 C^o, 60.509 C^o for January, April, July, and October. This was remarkably important in terms of Solar Energy on the extent of utilization of water evaporation temperature.