Solar evaporation performance of 3D-printed concave structures filled with activated carbon under low convective flow

Three-dimensional (3D) geometries were 3D-printed to make unique geometries filled with activated carbon to improve water transport and photothermal conversion when used as solar evaporators. Evaporation was modelled to study the different aspects affecting the evaporation performance of five geometries. Low convection airflow, concave surface evaporation, light reflection and natural convection were investigated in a 2D flat surface and four 3D structures presenting a concave surface. It was revealed that the effect of surface-to-surface radiation has a limited impact on the evaporation rate (1%), which depends linearly on the evaporation area. We have undoubtedly shown that, both in forced and natural convection, concavity in the structure should be avoided as it leads to moisture-saturated air. On the contrary, the 3D structure should be as open as possible to allow the unsaturated air to escape.

Automated summary

In this study, 3D-printed geometries filled with activated carbon were used as solar evaporators to enhance water transport and photothermal conversion. The effect of low convection airflow, concave surface evaporation, light reflection, and natural convection on the evaporation performance was investigated. It was found that surface-to-surface radiation had a limited impact on the evaporation rate, which depend linearly on the evaporation area. The results showed that concavity in the structure should be avoided as it leads to moisture-saturated air, and the 3D structure should be as open as possible to allow the unsaturated air to escape.