土壤消毒机蒸汽输送装置的设计与数值模拟

土传病虫害严重制约了设施栽培的发展。蒸汽消毒相比于其他土壤消毒方法,具有诸多优点,其利用高温杀死土壤中的病虫草害,提高了土壤的通透性和排水性,且对环境无任何污染。为此,基于脉冲式土壤蒸汽消毒机的总体结构,重点对蒸汽输送装置的注射针头以及蒸汽罩盖、针头间距、针头数目等蒸汽盘关键结构参数进行了设计。利用Fluent软件对土壤传热模型进行了数值模拟,分析了注射针头周围土壤的温度分布云图。结果表明:持续施加蒸汽7min、停止通蒸汽35min后,在半径10cm内、深度21cm范围内,土壤的温度能保持在90℃以上,验证了蒸汽输送装置结构的合理性。

Design and Numerical Simulation of Steam Transfer Device for Soil Disinfector

Soil borne diseases and pests seriously restrict the development of facilities cultivation. Compared with other soil disinfection methods, steam disinfection has many advantages. High temperature steam was used to kill the pests and grass in the soil, and the permeability and drainage of the soil was enhanced. This method has no pollution to the environment. Based on the overall structure of pulse type soil steam sterilizer, the key structural parameters of steam tray, such as syringe needle, steam cover and distance between needle and number of needle, were designed. The numerical simulation of soil heat transfer model was carried out by Fluent software. After applying the steam for 7min, the temperature of the soil can be kept above 90 degrees C within the radius 10cm and the depth of 21cm. This study validates the rationality of the structure of the steam conveying device.