Investigation of Novel Fibre-Tubes Indirect Evaporative Air Cooler

Direct evaporative cooling often results in increased relative humidity, which may lead to poor thermal comfort. Indirect evaporative cooling offers a solution but its efficiency requires improvement. Fibrous materials are widely used for indirect evaporative cooling but these have only a limited capillary effect. If the cooler is to be positioned vertically, periodic spraying with water is required to operate the cooler. This process adds to power consumption and increases operation costs, as well as construction and operational complexity. A new idea of using a horizontal arrangement has been considered. This eliminates the need for a pump to supply water. A horizontal system has been constructed and tested under various temperatures, relative humidities and air flow rates. Results showed that a 6-10°C temperature drop between the inlet and outlet of the product (supply) air could be achieved without an unwanted rise in relative humidity. The increase in relative humidity of the product (supply) air was much less than that of the working air. The fibre tube evaporative cooler has the potential to cool a building space with very little addition of moisture.