Abstract: The 3-D numerical simulation was utilized to study temperature distribution of the greenhouse under natural ventilation in winter based on the experimental observation of the solar greenhouse with tomatoes in Jinan. The temperature distribution was obtained using the computational fluid dynamics (CFD) numerical techniques with the support of the standard κ_ε turbulent model and the discrete ordinates (DO) radiation model. The results showed that the CFD numerical techniques could generate a satisfactory simulation of the temperature variation of the naturally ventilated solar greenhouse. The average error between the simulated and actual temperature was 0.9 ℃. In the sunny days in winter, the temperature of the greenhouse could reach the suitable level for crop within 16-23 min under the conditions of the different wind directions and the corresponding average wind speeds in Jinan. The temperature difference was around 3 ℃ between the temperatures in the north and south and around 4 ℃ between the east and west when the wind direction was NE, ENE, E, ESE, SE, SW. The temperature difference was around 4 ℃ between the north and south and around 1 ℃ between the east and west when the wind direction was SSW. Our results could provide a scientific reference to the structural optimization and the production management of the solar greenhouse.

Key words: protection efficacy evaluation, indicator system, ecological effectiveness, management effectiveness, wildlife protection, nature reserve management.