Analysis of various design parameters of a desert cooler

ABSTRACT

Aside from climatic parameters, the cooling potential of a desert cooler is influenced by fan flow rate, pad thickness, and pad packing factor, all of which are referred to as cooler parameters. In this study, a general equation for determining cooling potential in terms of cooler parameters is proposed and validated. An equation has been devised to determine the combination of fan flow rate (FFR) and pad area required to meet a given heating load. The equation aids in the sizing of coolers for a desired room temperature in various climates. The size of the cooler tank is determined by the rate of water evaporation. In this investigation, we evaluated the influence of different fan flow rates on the rate of water evaporation. It is seen that at a typical set of climatic parameters and for a given pad (1 m², 350 m²/m³, 10 cm thick), the cooling potential of the cooler increases by increasing fan flow rate ($\mathrm{FFR}\le 1.1{\mathrm{m}}^3/\mathrm{s})$. Furthermore, increasing pad area reduces the amount of fan flow rate required for a given heating load, allowing one to select the appropriate combination of fan flow rate and pad area. Higher fan flow rates increase the running cost, while increasing pad area raises the initial investment cost. The pad area needed (10 cm, 350 m²/m³) for the composite climate of Delhi at a 0.35 m³/s FFR, is roughly 66.7% less than that for the hot climate of Jodhpur for 4 kW heating load.

KEYWORDS:

• Cooler parameters
• cooling potential
• cooler size
• direct evaporative cooler
• evaporation
• fan flow rate

Nomenclature

Table

Acknowledgements

We would like to thank Prof. M. S. Sodha for giving us valuable suggestions during work.

Disclosure statement

The authors affirm that they have no known financial or interpersonal conflicts that would have seemed to have an impact on the research presented in this study.