Nanofluid-based wick-type integrated solar still for improved diurnal and nocturnal distillate production
Jagteshwar Singh, Madhup Kumar Mittal, Vikrant Khullar
Abstract
In the present work, a novel “nanofluid-based wick-type integrated solar still” has been designed, fabricated, and tested under on-sun conditions to assess its diurnal and nocturnal performance characteristics. Herein, floating wicks were placed inside the basin of single slope-single basin solar still. Furthermore, the basin water was supplied with external thermal energy collected by a nanofluid-based volumetrically absorbing solar collector (NBVASC) during the sunshine hours (9 am to 6 pm) and from the solar pond during the non-sunshine hours. In essence, the benefits of volumetric as well as surface heating have been synergized to significantly enhance the distillate production rate. Volumetric or bulk heating allows for enhanced sensible heat storage in the NBVASC, and the presence of wicks in the still’s basin lends localized surface heating of basin water – thus considerably improving the evaporation rates. Rigorous on-sun testing of “nanofluid-based wick-type integrated solar still” showed significant improvements relative to the conventional solar still; distillate productivity and efficiency enhancements on the order of 111.1% and 89.9%, respectively, were recorded (with exergy efficiency of 3.40%).