A dimensionless parameter coupling the south and north roofs on the thermal environment of Chinese solar greenhouse: Ridge position ratio

This paper clarified the mechanism of the south and north roofs on the thermal environment of the Chinese solar greenhouse (CSG), using a new parameter: ridge position ratio (RPR), which can describe the dynamic dependency relationship between the south and north roofs. A mathematical model was established by using the method of combining computational fluid dynamics (CFD) with experiments, which then was used to analyze the effect of RPR on the thermal environment of the CSG. Based on this model, we compared the temperature distributions of the greenhouse with different RPR. Furthermore, the effects of different RPR on the amount of solar energy that entered the greenhouse were studied. Finally, the effects of different RPR on heat released capacity of the greenhouse envelopes at different moments were analyzed. The results showed the decline rate of the maximum temperature of each part in different RPR intervals increased as the increase of RPR during the daytime. The occurrence time ...