M.T. Chaibi^1,, K. Bourouni², M.M. Bassem³

The paper reports the results of pilot test on the cooling performance of a direct cross flow mechanical cooling tower located in the Kebili region in the southern part of Tunisia. In this study heat and mass transfer data are measured within the tower over a period of one year and compared with external weather data collected over the same period. The data enabled the influence of different weather conditions on the performance of the cooling tower to be analyzed. The results obtained show that ambient humidity has a greater influence on performance than external temperature. In fact, significantly better cooling performance of about 80% was obtained during the high temperature, low humidity summer months than during the winter period, less than 40%, with relatively low external temperature and high humidity. These results indicate the relative importance of evaporative cooling as compared to convective cooling. The effect of wind on cooling performance was found to be considerable but was confined to those periods when wind direction coincided with the orientation of the louvers of the tower. This was observed to occur only during the summer period when compared to winter period, thus attesting the benefits of the use of proper cooling tower design for improving efficiency and conserve energy.

mechanical cooling tower, cross flow, cooling efficiency, evaporative cooling, convective cooling, geothermal water, south Tunisia