基于动态传热模型的车载LNG气瓶日蒸发率检测

Detection of Daily Evaporation Rate of On-vehicle LNG Gas Cylinder Based on Dynamic Heat Transfer Model

车载LNG气瓶是一种储存低温液化气体的低温绝热气瓶装置,其标准日蒸发率测试过于耗时,给使用单位的正常运行带来很大困扰。将辐射传热简化为热传导传热,建立了静置阶段和测试阶段的传热模型,求解了日蒸发率的解析式,并与实际检测数据进行了对比。结果表明,模型与检测数据相符合,提高充装量可以缩短静置时间,气瓶内胆材料的热容是产生长静置时间的原因。

The on-vehicle LNG cylinder is a cryogenic insulation cylinder device for storing cryogenic liquefied gases.The standard daily evaporation rate test is too time-consuming,which greatly hinders the normal operation of the user unit.In this paper,a dynamic heat transfer model,for standing section and testing section,is developed and simplified by replacing radiant heat transfer with thermal conduction.The model is solved and compared with experiment data.As shown by result,the model fits data well,and higher filling quantity leads to shorter standing time,and the heat captain of the inner material is the main reason to long standing time.