Calculating And Simulating The Shapes Of Reflecting Film Of Sunlight Greenhouses In Chongqing

Greenhouse is a main type of protected agriculture, according with the development of modern agriculture. Light conditions within sunlight greenhouses has great influence on the crops, especially for the crops on the ground, the radiation quantity and distribution are particularly important.Generally, distribution of luminous intensity on the ground inside greenhouses is uneven, so the different phenomenon of crops growth is appeared in North and South,In order to improve this phenomenon, the most extensively used measures is hanging polyester aluminum-plating reflecting film on the back wall. It can improve radiation quantity and distribution of luminous intensity greatly, for example, the difference in the shapes of reflecting film, length, height from the ground, will have certain effect on it. This paper is about distribution of luminous intensity of greenhouse which contacts tightly with the external environment and internal facilities. When the external light conditions and internal facilities in greenhouse change, the light conditions must also change. So it is necessary to study light conditions of greenhouse deeply.The paper summarizes the other’s research theory. Applying the knowledge of optics, meterology, architecture, etc and choosing different surface-shapes of reflecting film to set up light environment analysis model of greenhouse whether hanging a reflecting film or not. This model uses Visual Basic 6.0 language as the main programming tool. Analyzing the light conditions of greenhouse whether hanging a reflecting film or not, and comparing the light environment and hanging position when hanging different surface shapes of reflecting film based on existed programs. And simulation results is that the ideal surface shape of reflecting film is round surface and hanging position is 0.3m from the ground. This software which can be used to design lighting devices and measure performance has a certain value. And it also has certain significance on analyzing and improving the planting pattern of crops. At the same time, it has some value on developing products of greenhouse. It speeds up management level and work efficiency because of solving the experimentally derived data through computer program.