蓄冷保温箱真空隔热蓄冷控温传热模型与验证

为掌握不同参数对蓄冷控温特性的影响,建立了真空隔热蓄冷控温试验平台,以脐橙为试验对象,根据热平衡理论,建立蓄冷控温传热数学模型,并进行试验验证,进一步分析了不同参数对蓄冷控温特性的影响。数学模型计算结果表明,随着真空隔热板厚度的增加,在0~8℃温度的控温时间越长;当外界恒温30℃、真空隔热板厚度为25 mm时,0~8℃温区控温时长为106.14 h。试验结果表明,模型计算结果与试验结果吻合,控温时长平均误差为2.60%;当外界平均温度为33.5℃、真空隔热板厚度为20 mm、有太阳辐射时,在30 min内试验平台内温度由29.5℃降至7.2℃,降温速度较快。应用数学模型分析不同参数影响,结果表明:不同车速对传热速率的影响不显著;传热速率随着真空绝热板厚度的增加而下降,下降趋势呈指数变化;相同控温时长时,所需蓄冷剂质量与真空绝热板厚度呈指数变化;真空绝热板越厚,温度下降速率越快;太阳辐射会使控温时长缩短13.79%。该研究结果为蓄冷控温型运输装备的结构优化设计及蓄冷剂的选型、用量提供一定的参考价值。

Heat transfer model for vacuum insulated thermal cooling storage temperature control and verification in cold storage incubator

At present,phase-change cold storage incubator were mostly used for short-distance transportation,which was generally no more than 48 hours,and there are few researches on the influence of parameters such as heat insulation materials,cold storage materials and convective strength on the effect of cold-storage temperature control.In order to grasp the effects of different parameters on the temperature control characteristics of cold storage insulated box,which was made by vacuum insulating plate(VIP)creatively,a vacuum insulated cold storage temperature control test platform was established.The navel orange was used as the test object.According to the heat balance theory,the mathematical model of cold storage temperature control heat transfer was established,which mainly included the thickness of the vacuum insulation board,the velocity of vehicle,the quantity of the phase change material,heat transfer rate as well as the solar radiation Test results were verified and further analyzed.The mathematical model calculation results showed that with the increase of the thickness of the vacuum insulation board,the time which controlled temperature at 0-8℃increased.The temperature control time of the zone was 106.14 h,when the external temperature was 30℃,and the thickness of the vacuum insulation board was 25 mm,as well as the zone temperature was keep at 0-8℃.The model calculation results are consistent with the experimental results,and the average error of temperature is 2.60%.When the external average temperature was 33.5℃,the thickness of the vacuum insulation board was 20 mm,as well as the solar radiation was added,the temperature in the test platform decreased from 29.5℃to 7.2℃within 30 minutes,which showed that the cooling rate increased faster.The mathematical model were applied to analyze the effects of different parameters mentioned above.The results showed that the effect of different speeds on heat transfer rate was not significant.The heat transfer rate decreased with the increase of the thickness of vacuum insulation board,and the downward trend showed an exponential change.The quantity of the phase change material and the thickness of the vacuum insulation panel change exponentially under the same temperature control time.The thicker the vacuum insulation panel,the faster the temperature drop rate could be observed.The added solar radiation shortens the temperature control time by 13.79%.The research results provide a certain reference for the structural optimization design of the cold storage temperature-controlled transportation equipment and the selection and dosage of the cold storage agent.