Study On Climate Control Technology Of Venlo-type Greenhouse In Summer Based On Temperature Integration And Economic Optimization

In order to achieve the goal of continuable development such as high yield, high quality, low cost, high benefit and friendly environment, modern greenhouse should create a suitable environment for crop growth under changeful climate conditions. So more and more attention is paid to greenhouse, and it becomes a significant research direction. The control of the greenhouse microclimate is one of key techniques in modern greenhouse.The paper proposed method of the modelling taking into account the intelligent control of the greenhouse environment, based on the balance of the energy and mass.The energy and mass exchange physical processes resulted from radiation, ventilation,convection and crop transpiration in the greenhouse is discussed. The dynamic model of the temperature and humidity is built respectively. Secondly,The researching mateiral is cucumber, Jingyan 4,in this paper. With Collecting the environment data at certain time inside and outside of the greenhouse during cultivating the cucumber, the executable equipments' status and the physiological parameters of cucumber at different stages were recorded. With the method of Minimum Double Multiply, the relational function between the net photosynthesis rate and temperature, Light and CO₂ was established.What's more, it also establishes the costing model of environmental adjustment based on analyzing the adjusting cost of the facilities equipped by greenhouse.Finally, the whole crop cultivation season was divided into two periods,namely vegetative stage and reproductive stage. In vegetative stage, Temperature integration control was carried out to meet control requirements. In reproductive stage, the control strategies were acted as economic optimization methods. Putting control cost models, predicted environmental parameters control model and the crop growth models in unite system to maximize the greenhouse input/output as control objective. So it could create favorable microclimate parameters and conditions to fit crop growth and development. Practices showed that with the control system based on economic optimization strategies to manage crop growth and development, favorable control effects and lower cost were gained.The purpose of the research is to improve the intelligent level of greenhouse environment control. At the same time, this technique can ensure more theoretical and practical value in promoting the industrialization process of the greenhouse and accelerating sustainable development of protected agriculture.