In coal-fired power plants,the ambience wind speed and ambient temperature play an important role in determining the convective heat transfer between the cooling air and hot steam in the triangular cavity of the direct air-cooled condenser. Thus affecting the operational stability of the unit. In this paper,taking 600 MW unit single row/single air-cooled unit as an example,the performance of the direct air-cooled condenser was investigated by means of three-dimensional CFD under varied ambience conditions. Moreover,a novel "wing-type" solid/porous deflect plate with the adjustable angle in the triangular cavity to optimize the flow field of the condenser was proposed. The simulated results indicate that:the single row condenser is affected by the ambient wind effect,and the average air flow rate of the air condenser at the first position in the air inlet direction is most affected by the environmental wind speed. When the environmental wind speed increases from 3 m/s to 9 m/s,the average air flow rate of single column (consisting of 8 air cooling units) air condenser decreases by about 590 kg/s,indicating that the air disturbance increase and the heat transfer is unfavorable in the triangular cavity with high wind speed. The method of adding solid plate/porous plate in the condenser triangle cavity has obvious rectifying effect on the flow vortex generated in adverse environment. Besides,by adjusting the angle of the two plates to 240°,the static pressure in the triangular cavity has increased by 153 Pa on average,which can effectively alleviate the freezing phenomenon at the bottom of heat exchange tubes in the winter. This kind of direct air condenser with diversion device is suitable for a wide range of environmental conditions,which is beneficial to realize the functions of high temperature resistance prevention,low temperature anti-freezing and stable operation in practical engineering.