Investigation of the performance of a double-glazing solar distiller with external condensation and nano-phase change material

The solar still is a device that is simple in construction, easy to operate, and cheap in cost. However, the solar stills produce low amount of productivity. In this work, it was targeted that the solar still productivity is improved via using double-glazing with external condenser and nano-phase change material. These parameters are designed and chosen to achieve the aim of enhancing the evaporation and condensation processes of the solar still. Therefore, the impact of using various types of phase change materials (black marble and paraffin wax mixed with graphene nanoparticles) is also experimentally investigated. The tests' findings showed that employing double glazing raised the water and glass temperature of modified distiller by 1-6 degrees C and 5-20 degrees C higher than that of conventional solar distiller, respectively. Also, the modified distiller with double glazing covering had a 31.34 % lower productivity than the conventional distiller. Besides, using condenser with modified distiller improved the distillate by 23.59 % over that of the conventional distiller (2480 mL/m(2).day for conventional distiller versus 3065 mL/m(2).day for modified distiller with double glazing and condenser). Moreover, utilizing the black marble and nano-paraffin wax phase change materials in the modified distiller with double glazing and condenser improved the freshwater production by 83.33 % (4840 mL/m(2).day for modified distiller versus 2640 mL/m(2).day for conventional distiller) and 99.24 % (5260 mL/m(2).day for modified distiller versus 2640 mL/m(2).day for conventional distiller) respectively over that of the conventional distiller under the same conditions. Finally, the highest efficiency for modified distiller was achieved when using double glazing, condenser, and nano-paraffin wax phase change material, where it was 43.6 % compared to 30.5 % for the conventional distiller. These results demonstrate the effectiveness of the proposed modifications.