干旱区生态环境知识资源中心

An agricultural greenhouse is thermally analyzed using the simulation program TRNSYS 17. The thermal loads resulting from the heating and cooling are calculated to maintain the greenhouse temperature Within the range of crop development. Construction materials, geographical location and the optimal development characteristics of the Saladette tomato and its different growing stages are also reported. The thermal performance inside and outside the greenhouse with and without air conditioning is also described. The heating and cooling loads are shown for an idealized air conditioning system considering the number of heat exchangers, temperatures required by the crop and the hot/cold water temperature available in the system. The results of a thermal analysis for a three day in June is described in detail. The temperatures inside and outside of the greenhouse, including the thermal load for the most critical day of the year are shown. Simulation results show that 4,231,966 GJ and 39,324,140 arc being demanded for heating and cooling respectively along a typical meteorological year. A case of study is presented in order to analyze the greenhouse in which energetic requirement is partially provided using solar energy. The simulation shows that in order to achieve a solar fraction of 72% for heating and 30% for absorption cooling, 300 solar collectors are needed.