Improvement of Surface Evaporation by Reducing Heat Transfer to Fluid Bulk and Increasing Heat Absorption

Surface evaporation is important in many natural phenomena and industrial applications; Therefore, improving this phenomenon is very useful. In this research, the water evaporation rate is increased by designing an innovative structure by inspiring from plant structures. This structure has two main effects, firstly, it reduces the amount of heat transferred to the fluid bulk through the surface and secondly, it increases the amount of heat absorption on the surface. This structure consists of three parts: an evaporation layer, insulation, and water-absorbing fibers. After many investigations on different materials to choose the best materials for these three parts, expanded polystyrene foam and cotton fibers showed the best performance. The structure after construction and testing was able to increase the mass of evaporated water during 24 hours by 28%. It also increased the temperature of the water surface in the evaporation process during 24 hours by 16%; This caused the water to evaporate at a high temperature. In addition, the mentioned structure increased the thermal efficiency up to 85% in the radiant flux of 0.6 . The proposed structure is scalable for any size and cost-effective.