Investigation of the crosswind-influenced thermal performance of a natural draft counterflow cooling tower

The present work deals with an experimental investigation of the thermal performance of a natural draft wet-type cooling tower with counter flow arrangement. The authors perform a thorough analysis of the simultaneous heat and mass transfer phenomenon between air and water. The investigation mainly concentrates on the effect of crosswind on the thermal performance of the tower. Performance index parameters such as the temperature drop (Tdrop), effectiveness (e), and the tower characteristic ratio (KaV/L) are presented in the paper. Variation of the performance parameters in terms of inlet water temperature, water flow rate, and wind velocity is studied in a crosswind-influenced environment. When comparing the crosswind-influenced experimental data with that of the windless condition, it is observed that Tdrop and e decrease by 4% and 4.5%, respectively, in a crosswind environment. However, this decreasing trend of Tdrop and e is observed up to the critical Froude number, Fcr, followed by an increasing trend. Variation of the tower characteristic ratio in the crosswind environment for different values of inlet water temperature is also studied in detail. Two different regimes are found to exist as water and air flow within the tower. However, the capacity of cooling of higher water flow rates demonstrates that regime-II is more efficient than regime-I. Moreover, the correlative equations of different performance parameters are developed for both windless and crosswind conditions. Additionally, a correlation of tower characteristic ratio to different water-air mass flow rates is proposed.