Abstract: Abstract: As an indispensable design parameter in the large glass greenhouse complex (Venlo greenhouse), the installation height (minimum distance from the ground) of the wet curtain and fan in the mechanical cooling system plays a significant role in greenhouse performance. In order to address the issues of large vertical temperature difference, insufficient cooling, and insufficient cooling consumption that occur in the process of mechanical cooling of the wet curtain and fan of Venlo greenhouse in summer, the influence of different installation heights of the wet curtain and fan on the cooling effect of the greenhouse was analyzed using the method of combining experiment with numerical calculation in this paper. The experimental greenhouse was analyzed through a two-factor, four-level simulation design and range analysis of the different installation heights of the wet curtain and fan. The experimental method involved measuring data from the experimental greenhouse. The greenhouse is a butterfly-shaped glass greenhouse located in Kemulang, Tianhe District, Guangzhou, which was newly built in 2019 in the Demonstration Base of Guangdong Agricultural Technology Extension Center, and equipped with a mechanical cooling system, including wet curtains, fans, and environmental data collectors. The experimental data was collected in August 2021, and the numerical calculation method was based on CFD. 16 different combinations of the installation heights of the wet curtain and fan were simulated for the greenhouse. The installation heights were 0.8, 1.6, 2.4, and 3.2 m. Data was processed by using the range analysis method, with the average temperature of each installation height serving as the evaluation standard for the cooling effect. The simulation method was verified, with an average temperature error of 1.5?℃ for the simulation model. The simulation model was also verified for cell independence, with an average error of 1.8?℃ when the number of cells increased and an average error of 0.9?℃ when the number of cells decreased. The results showed that within the 3.2?m installation height: Simulation program 4, that was when the wet curtain installation height was 0.8?m and the fan installation height was 3.2?m, had the most obvious cooling effect, with the average temperature of the greenhouse reduced by 2.1?℃; the maximum temperature vertical gradient in the greenhouse was 8.1?℃, which was 6.4?℃ lower than that in the experimental greenhouse; the average temperature vertical gradient was 7.1?℃, which was 4.3?℃ lower than that in the experimental greenhouse; when the wet curtain installation height was 3.2?m and the fan installation height was 3.2?m, the temperature vertical gradient was the smallest, and the average temperature vertical gradient of the greenhouse was reduced by 5.8?℃. It can be seen through the analysis that raising the installation height of the wet curtain and fan can cause the flow field of the wet and cool air to flow towards relatively higher positions in the greenhouse, providing better cooling for higher crops in the greenhouse. However, due to the characteristic of the downward flow of wet and cool air, the upward flow of the flow field is relatively limited, and the enhanced cooling effect is limited. Compared with the experimental greenhouse, the change in the installation height of the wet curtain and fan does indeed affect the overall cooling effect of the Venlo greenhouse. Properly reducing the installation height of the wet curtain and increasing the installation height of the fan can allow the flow field of wet and cool air in the greenhouse to flow and diffuse more thoroughly, so as to strengthen the heat exchange process; however, the impact of flow field changes on wind speed, humidity, and other factors still needs to be considered.