Zhirong Zou, Yong Zhang
College of Horticulture, Northwest A&F University
This paper introduce three type solar-greenhouses, the innovation structure were the tilting roof solar-greenhouse, the active thermal-storage back wall solar-greenhouse and the normal solar-greenhouse respectively. Comparing to the normal solar-greenhouse, the tilting roof solar-greenhouse has new form roof with adjustable tilt angle, and the active thermal-storage back wall solar-greenhouse has new active thermal-storage back-wall respectively. This paper studies and analyzes the experimental data by experiment comparison and lighting analysis method. The temperature and the solar irradiance changing rate indoors and outdoors of solar-greenhouse was analyzed theoretically in this paper. Then it puts forward a new structural model of high-performance greenhouse.
Through the research, under this experiment condition the tilting roof solar-greenhouse is more efficient in utilization of solar energy and raising temperature. Illumination and indoor temperature in the greenhouse with active tilting roof & thermal storage technology has a great enhancement comparing with normal type. The average increasing rate of lighting performance is 47.3%(68w/m2) in the tilting roof solar-greenhouse and 16.9%(25w/m2) in the active thermal-storage back wall solar-greenhouse within 09：00 ～16：00. Synthesized every indexes, the solar-greenhouse with adjustable tilt angle may be the most economic structure; it can improve the day-lighting performance by 30.4% (43w/m2) than the solar-greenhouse with fixed roof angle and the same height-span ratio. Comparing with normal type, the mean indoor temperature increases is 4.3℃ in the greenhouse with active tilting roof and 6.0℃ in solar-greenhouse with active thermal storage type at this experiment condition. Comparing with the solar-greenhouse with active thermal storage type, the mean indoor temperature decreases is 1.7℃ in the greenhouse with active tilting roof.
This paper, according to indoor day lighting analysis, based on an indoor average temperature, presents the influence coefficient of active day lighting& thermal storage technology, analysis the significance and skill of solar energy utilization in the design of new solar-greenhouse structure. And it provides the theoretic foundation and experiment results on the efficient utilization of Solar Energy and the improvement of greenhouse structure management.
|
