Experimental study of natural materials for an evaporative cooling design in hot-arid climate

Abstract

An experimental test was set up in the hot arid Seiyun city, Yemen to assess the cooling performance of three-case materials used as a wetted medium for a bio-inspired cooling design installed in a wind tower. The cases design materials are (i) clay plates, (ii) clay with jute fiber and (iii) clay with wood wool. Additionally, the study examined the effect of design height and the number of wood wool pads on the cooling efficiency. The performance criteria are based on the cooling efficiency and pressure drop of each case design under 6 air velocities range from 1.0 to 3.5 m/s. The results showed that the average cooling efficiency for the three-case materials is highest for the design of clay with jute fiber 85.2%, compared to 76.6% for clay with wood wool, and 66.3% for the clay design. The clay with wood wool was the highest medium to drop air pressure which ranged from 11 to 33.5 pa, followed by clay design with a drop varied from 5 to 30 pa and the lowest was performed by the design of clay covered by jute fiber which ranged from 2.5 to 27.5 pa. The study also found that the cooling ability of the design increases with the increment of its height and the number of wood wool pads. This study concluded that the cooling designs can replace the HVAC systems in the hot arid regions which will significantly contribute to energy saving and environment protection.