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

Abstract: 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