## 5 Conclusions  
Under windless conditions, the wind entering the tower is uniform. However, as the crosswind speed increases, the air flow rate and heat transfer rate of the air-cooling tower decreases and then increases. Therefore, the idea of rotating wind deflectors is proposed and found to be efficacious for saving energy on radiator heat transfer in the air-cooling tower according to the numerical simulation and experimental results. The following conclusions are drawn. (1) Crosswind has great influence on air-cooling tower performance. The worst point occurs at a crosswind speed of 5 m/s, at which point the heat transfer rate and air flow rate decline by 32.4% and 62.5%, respectively. Figure 21: Comparison of thermal efficiency coefficients from experimental and numerical simulation results with rotating wind deflectors. (2) Compared with conditions without wind deflectors at a crosswind speed of 5 m/s, the air flow rate and heat transfer rate of the tower increase maximally by 61.7% and 15.1%, respectively, when eight wind deflectors are arranged at the bottom of the cooling tower. (3) The thermal-hydraulic and cooling performance of the air-cooling tower are enhanced by rotating wind deflectors. An air-cooling system with rotating wind deflectors is complex; hence, the relevant mechanisms and applications warrant further study with attention paid to thermal-hydraulic, energy-saving, pump consumption, space-saving, and economic performance. This work is supported by the Fundamental Research Funds for the Central Universities (No. 2015 XKMS059). [PERSON] designed the experiment system, conducted the model experiment, and wrote the manuscript. [PERSON] proposed the numerical simulation model, analyzed the results, and checked and revised the whole manuscript. [PERSON] finished the numerical simulation and collected the experimental data together. The authors declare  
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