Augmentation of hemispherical solar distiller performance utilizing ultrasound atomizers and carbon black nanoparticles

•The distillate yield with four atomizers and 1 cm water height was 3.966 L/m2.•The integration of the on–off timer with HUA produces 6.393 L/m2 with an improvement rate of 107 %.•The maximum distillated yield (7.321 L/m2) was achieved utilizing nanoparticles with HUA and on–off timer.•The proposed system peek value of energy and exergy efficiency was 44.22% and 3.81%.•The estimated cost varied between 0.0128 and 0.0205 USD/L. Addressing the water shortage and environmental concerns, this study suggests several modifications to the hemispheric solar still aiming to increase productivity while maintaining a competitive water price. The distiller is enhanced with an ultrasonic atomizer to improve water evaporation throughout the day. The study investigates the impacts of both the water height above the atomizers and their quantity. The system performance was investigated under three cases of modified design, Case 1; integration with atomizers, Case 2; combined atomizers with on–off timer, Case 3; augmented carbon black nanoparticles with atomizers and timer. Results indicated that with four atomizers and 1 cm water height above them, the productivity reached 3.966 L/m2, with exergetic and energetic efficiencies of 1.87 % and 23.22 %, respectively. Additionally, an on–off timer is incorporated into the unit to test performance under different on–off durations (15 min, 20 min, and 25 min). With a 20-minute interval, these values escalated to production rate, energy, and exergy efficiency. 6.393 L/m2, 38.75 %, and 2.95 %, respectively. Furthermore, carbon black nanoparticle implementation is integrated into the distiller alongside intermittent atomizer operation. This integration further boosts productivity to 7.321 L/m2, significantly improving exergy (3.81 %) and energy efficiencies (44.22 %). Compared to a non-modified hemispheric distiller, the modified distillers show productivity enhancement ratios of 40.5 %, 104.1 %, and 137.1 % for the three cases, respectively. From an economic perspective, the water price is substantially lower for the modified distillers, ranging from 0.0128 to 0.0205 USD/L, compared to 0.0229 USD/L for the traditional distiller.