论文部分内容阅读
连栋塑料温室主要依靠日光蓄热,冬季为保温需要长时间密闭以避免室内热量流失,这就导致室内形成高湿环境,使栽培作物易患病虫害。以有效除湿和减小室内热量损失为目标,以十一连栋塑料温室为研究对象,建立全尺度计算流体力学模型(CFD模型)。在顶窗通风工况下,CFD模型的有效性经实验数据验证,其计算值与各测点湿度的实验值变化趋势吻合,且差异在5%以内;并利用该模型研究了不同开窗组合(侧窗、顶窗和顶窗加侧窗)对温室内空气流场和湿度场的影响。仿真结果表明,顶窗通风是一种较理想的通风组合,能够在3 min内完成作物冠状层的除湿。除湿结束后,室内平均相对湿度从92%降至68%,湿度分布均衡性较好,且热损失较小,能满足冬季温室保温、除湿的要求。
Multi-span plastic greenhouses rely mainly on solar thermal storage, winter insulation for a long time to be sealed to avoid indoor heat loss, which led to the formation of indoor high humidity environment, making the crop susceptible to pests and diseases. In order to effectively dehumidify and reduce indoor heat loss, a full-scale CFD model was established with eleven multi-span plastic greenhouses as the research object. The effectiveness of the CFD model is verified by experimental data under the roof window ventilation conditions. The calculated values are in good agreement with the experimental values of the humidity at each measuring point, and the differences are within 5%. Using this model, (Side windows, top windows and top windows plus side windows) on the air flow field and humidity field in the greenhouse. The simulation results show that the roof ventilation is an ideal combination of ventilation, which can complete the crop crown dehumidification within 3 min. After the dehumidification, indoor average relative humidity is reduced from 92% to 68%, the humidity distribution is well balanced and the heat loss is small, which can meet the requirement of heat preservation and dehumidification in winter greenhouse.