Study on the Discharge Coefficient of Wind-Driven Naturally Ventilated Chinese Solar Greenhouses

The Chinese solar greenhouse (CSG) is a prevalent feature in agricultural practices within China. Nevertheless, the regulation of natural ventilation within this architectural structure remains suboptimal. Consequently, the development of a natural ventilation model becomes imperative for the effective management of the greenhouse environment. Of particular significance within these models is the consideration of the discharge coefficient as a pivotal parameter. Conducting a multi-case investigation into the variable-dependent discharge coefficient is crucial for both practical application and model advancement. This research delved into the impact of various factors, including the upper-lower vents area ratio (Aup/Alow), vent-greenhouse area ratio (Alow/Agreenhouse), lower vent position height (h/H), the incident angle of the external wind, and altitude, on the discharge coefficient (Cd) of CSG. A CFD model was developed for a scaled CSG with validation conducted through field experiments and wind tunnel tests. Results indicated a 61.6