Thermal environment model construction of Chinese solar greenhouse based on temperature–wave interaction theory

Chinese solar greenhouse (CSG) is an important energy-saving building to ensure the winter production of crops, but it still faces the problem of unbalanced supply and demand between actual thermal performance and crop temperature demand. The purpose of this study is to establish the relationship between greenhouse thermal environment simulation and thermal performance design and to put forward specific thermal performance requirements for the main heat storage components (walls) in the greenhouse design stage. Therefore, this study proposed a method to construct the thermal environment fluctuation model of Chinese solar greenhouse based on temperature-wave interaction theory. The method used dimensional analysis method to comprehensively analyze the related physical quantities of greenhouse thermal environment, explored the temperature fluctuation interaction among indoor air, energy storage wall and outdoor air, and constructed the thermal environment fluctuation model of Chinese solar greenhouse. Finally, the thermal environment fluctuation equation of Chinese solar greenhouse was established under the external climatic conditions in Xi'an, Shaanxi Province, and verified by the measured data of the experimental greenhouse. The experimental results show that the mean absolute error (MAE) between the predicted and measured indoor air temperature is 0.66 °C, the root mean square error (RMSE) is 1.04 °C, and the determination coefficient (R2) is 0.9956 (n = 2822). The model and equation accurately described the interaction between greenhouse internal components and the external greenhouse environment. The study put forward specific thermal performance design requirements for the main heat storage components (walls) in greenhouse, and also provided a new research method for the thermal environment model of Chinese solar greenhouse.