液氮充注气调保鲜运输试验平台的设计

Design of an Experimental Platform with Controlled Atmosphere by Liquid Nitrogen Injection for Food Transportation

针对液氮充注气调时瞬间冷能释放大及气调保鲜环境均匀性要求高等特点,结合液氮充注气调装置、加湿装置、温控机组、换气装置等的结构特点,采用有机玻璃设计加工了基于压差的厢体结构。该平台可调节回风道长度、开孔隔板开孔率、汽化盘管长度、通风风速、箱体气密性等参数;开设厢体后门方便货物堆栈,开设厢体前门便于调节设备工作参数;厢门开启处采用中性硅酮密封胶密封,气密性良好。该试验平台可调节保鲜厢体内温度、湿度和气体成分等参数,为液氮充注气调保鲜运输装备的开发奠定了基础。

A container was made of Plexiglas panels and based on the pressure difference to meet the character of liquid nitrogen（LN2） which released large amount of cold energy during controlled atmosphere（CA） and to provide a uniform flow field therein.The structures of relevant appliances,such as LN2 injection equipments,humidification equipments,refrigeration equipments,were also taken into consideration for the design of the container structure.The important experimental parameters,including the air return channel length,the opening rate of the perforated partition,the ventilation velocity,and gas tightness of the container,were designed variable to facilitate the following experiments.The back panel was able to open to stack the cargos and the front panel was dismountable to adjust the parameters of the equipments inside.The neutral silicone sealant was used to seal the container,which was proved of good air tightness character after a leakage test.This experimental platform could control the temperature,humidity,and gas composition in the container,which helped develop the fresh-keeping transportation vehicles with CA system by LN2.