茼蒿真空预冷过程捕水器捕水特性理论分析及预冷工艺试验研究

Theoretical analysis on vapor condensation characteristic of vapor condenser and experimental study of pre-cooling technology in vacuum pre-cooling processes of garland chrysanthemum

基于大叶茼蒿真空预冷过程捕水器的换热特性,通过对捕水器的换热机制、捕集水量进行研究与计算,分析了制冷系统的不同蒸发温度对捕水器捕水能力和制冷系统压缩机功耗的影响问题,试验研究了预冷压力和表面喷水量对大叶茼蒿预冷效果的影响。结果表明:大叶茼蒿在真空预冷过程,制冷系统最佳蒸发温度为-5℃,捕水器的单位能耗捕集的水量最多为29.2 g/W;大叶茼蒿最佳真空预冷条件为预冷压力900 Pa、表面喷水量为5%,预冷后可保持15 d的货架期,结果可为捕水器的设计思路、寻求大叶茼蒿的最佳预冷工艺条件和延长其冷藏保鲜期提供理论依据。

Based on the vapor condenser＇s heat transfer characteristics and mechanism, through the calculation of trapping water, the effect on the ability of condensation and compressor power consumption of refrigeration system of different evaporation temperature was analyzed. And the effect on garland chrysanthemum pre-cooling of pressure and surface spray was studied. The result showed the best evaporation temperature was-5 ℃, energy consumption per unit of water trapped vapor condenser was up to 29.2 g/W. The optimum vacuum pre-cooling condition was that： the pre-cooling pressure was 900 Pa, surface spray was 5%. Under the condition, garland chrysanthemum could maintain 15 days shelf life. The result might provide design idea of vapor condenser, and theoretical basis for prolonging the garland chrysanthemum＇s storage period of refrigerated.