Effect of Inlet Window Deflectors on the Performance of a Natural-Draft Cooling Tower Subjected to Crosswinds

Abstract

The effect of inlet window deflectors on the performance of a natural draft cooling tower subjected to a crosswind was studied numerically. Three patterns of the inlet window deflectors with different setting angles (62, 72, and 82 degrees) were tested under various crosswind velocities. The assumption of heat and mass transfer equivalence was adopted for simulation. A numerical model was developed and verified by comparison with experimental data. The simulations show that the 72-degree inlet window deflectors are efficient in a wide range of crosswind velocities. The effect of the number of deflectors was also investigated and the link between the velocity profile and the critical wind velocity was clarified. It was shown that the use of deflectors in the inlet window increases the thermal efficiency of a cooling tower up to 8.6% at wind velocities greater than 2 m/s and does not exhibit any effect at the wind velocities close to critical wind velocity. The investigation may be helpful in optimal design of natural draft and “hybrid” cooling towers.