[Objective] This paper aims to solve the problems of backflow and air flow competition caused by air in the non-water distribution area of the “dual-unit and single-tower” type high-position tower. [Methods] A threedimensional numerical model of constant heat load is established and verified by taking the high-position tower of a 2×1 000 MW unit in a power plant as the research object. Under the condition of no wind and dominant wind speed

the influence of different water distribution schemes on the air flow field

thermal parameters and water temperature field in the tower is analyzed

and the optimization mechanism of water distribution scheme is obtained. [Results] The results show that under the condition of no wind

the air velocity in the area without water distribution is very low

and the phenomenon of air flow deflection and short circuit is serious. A large area of low-speed vortex is generated in the throat under crosswind condition. Different water distribution schemes affect the effective ventilation volume by modifying the aerodynamic field in the tower

which further causes the difference of effective air-water ratio and outlet water temperature. Under the condition of no wind

the effective air-water ratio is positively correlated with the water distribution area. Under the condition of crosswind

the thermal performance of the highposition tower is affected by the water distribution area and the water distribution position. With the crosswind speed of 2.7 m/s

the effective ventilation rate and effective air-water ratio of Scheme 3 with water distribution on the windward side are 4 111 kg/s and 0.16 higher than those of Scheme 2 with water distribution on the leeward side

respectively. The peak value of the high temperature zone reduces by 1.98 ℃

and the outlet water temperature is 0.63 ℃ lower than that under no-wind conditions. [Conclusion] By optimizing the water distribution position

expanding the water distribution area and selecting water distribution on the windward side

the wind speed at the tower inlet can be increased

the short circuit of the air flow can be reduced and the effective ventilation volume can be increased

so as to improve the wind resistance of the high-position tower and reduce the outlet water temperature.