Wind-induced interference effects of two large cooling towers with air-deflectors

In order to study the effect of different air-deflectors on surface wind load of two cooling towers, investigations for large cooling towers are conducted by three wind tunnel tests with the air-deflectors and one without the air-deflector on wind pressure characteristics including the mean wind pressure, fluctuating wind pressure, peak factor, extreme wind pressures, and interference factors. Results show that, additional air-deflectors lead to negative pressure airflow disturbance in the leeward area of the towers, and significant fluctuations are observed in the mean wind pressure. Additional air-deflectors have significant influence on the peak factor of the lower sections, however, insignificant influence is observed on the measurement points in upper sections. The values of the peak factor are between 3.2 and 3.6. The extreme wind pressure distributions display a symmetric mode, which is similar to the mode of cooling tower. The extreme wind pressure increases by about 0.5 on the cooling tower at the throat sides with external sink. A 90-degree wind direction is the worst condition for the two towers, since the mean wind pressure, the fluctuating wind pressure, and the extreme wind pressures at tower sides significantly change due to the channel-effect. The interface factors reach its maximum values in the upper sections on the cooling tower with external sink.