PERFORMANCE OF DIRECT EVAPORATIVE COOLING SYSTEM UNDER EGYPTIAN CONDITIONS

Khater, El-Sayed G.

doi:10.21608/mjae.2014.98420

PERFORMANCE OF DIRECT EVAPORATIVE COOLING SYSTEM UNDER EGYPTIAN CONDITIONS

Document Type : Original Article

Author

El-Sayed G. Khater

Lecturer. of Agric. Eng., Fac. of Agric., Benha Univ., Egypt.

10.21608/mjae.2014.98420

Abstract

The main objective of this research is to optimize the parameters affecting the performance of the evaporative cooling system, to achieve that, a mathematical model of heat and mass balance of the evaporative cooling pads was developed to predict most important factors affecting the performance of the system.The model was able to predict the temperature, humidity ratio, wet bulb effectiveness, dew point effectiveness and temperature-humidity index of outlet air at different ambient air temperatures (25, 30, 35 and 40°C), different inlet air velocities (1.5, 3, 4.5 and 6 m s^-1), ambient air humidities (0.01, 0.02, 0.03 and 0.04 kg kg^-1) and different lengths of pad (0.5, 1.0, 1.5 and 2.0 m). The results showed that the outlet temperature increases with increasing ambient temperature, inlet air velocity, ambient air humidities and lengths of pad. The results also showed that the wet bulb effectiveness decreases with increasing ambient temperature, inlet air velocity, ambient air humidities and it increases with increasing lengths of pad. On the other hand, the dew point effectiveness decreases with increasing ambient temperature, inlet air velocity, ambient air humidities and it increases with increasing lengths of pad. The humidity ratio decreases with increasing ambient temperature and inlet air velocity and it increases with increasing ambient air humidities and lengths of pad. The temperature-humidity index increases with increasing ambient temperature, inlet air velocity, ambient air humidities and lengths of pad. The predicted outlet temperatures were in a reasonable agreement with those measured, where, it ranged 17.027 to 29.978 °C theoretically while it was from 19.605 to 30.748 °C experimentally.

Keywords

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