The random distribution model (RDM) and uniform distribution model (UDM) were used to simulate the thermal sterilization of canned fruit. The RDM was established with the radiation function, and the stability of RDM results was analyzed by simulating temperature change during thermal sterilization and determining the sterilization parameter F value of the slowest heating zone (SHZ). The performance of the distribution models in simulating thermal sterilization heating process of canned fruit with different shapes was studied using the UDM and RDM of canned yellow peach (hemispherical shell), pear (sphere), and coconut (cube). Simulation results were compared with experimental results. The flow field and temperature field distributions were used in analyzing the influence of fruits shape on the accuracy of the models. The simulation results of different RDMs were consistent with the temperature change and F value, indicating that the RDMs had stable simulation results. When the contact between two types of fruit was a point, the UDM can be used in the numerical simulation of thermal sterilization. When the contact was a non-point, the RDM was more accurate in simulating thermal sterilization. This study provides constructive suggestions for the simulation of thermal sterilization of canned fruit with different shapes.

The storage time of cold box is an important subject. At present, the research method of the storage time is mainly experiment, and the theoretical research is incomplete. Therefore, in this work, a theoretical modeling combined with a network method of radiation heat transfer, shape factor of heat conduction, and sensible heat of refrigerant was proposed to calculate the storage time of a cold box at various ambient temperatures and amounts of refrigerant. The experimental and simulation results were used to verify the theoretical modeling of the storage time. The influences of sensible heat of refrigerant and radiation heat transfer in the cold box were analyzed. The stability of the theoretical modeling was studied via simulation of the different cold box and refrigerant materials. The results of the accuracy of theoretical model confirmed that the maximum error between the theoretical and the experimental storage times is 8.45%, and error between the theoretical and the simulation results is 7.51%, indicating that the sensible heat of refrigerant and radiation heat transfer have big impacts on the storage time. The stability of theoretical model is confirmed under different box and refrigerant materials. The storage time model has stability on different box materials and refrigerant materials. The theoretical model can be severed as a fundamentally guidance for the cold box production design.

The storage time of cold box is an important subject. At present, the research method of the storage time is mainly experiment, and the theoretical research is incomplete. Therefore, in this work, a theoretical modeling combined with a network method of radiation heat transfer, shape factor of heat conduction, and sensible heat of refrigerant was proposed to calculate the storage time of a cold box at various ambient temperatures and amounts of refrigerant. The experimental and simulation results were used to verify the theoretical modeling of the storage time.