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Temperature is one of the key factors for maintaining the quality of fruits and vegetables during storage or transportation. Improving airflow in the container is beneficial for adjusting the temperature in a container quickly and effectively. 3-D numerical models, which combined with the theory of porosity media, were built to investigate the temperature distribution in a 40 feet container. The thermal characteristics of litchi products and the container wall were considered in the models. Totally 12 models, including different air-outlet duct velocities, porosity areas and hole locations on the air-outlet duct, were conducted to study the effects of those factors on change of air and products temperature during the cooling process in the container, by which the airflow characteristics in the container were obtained and analyzed. After comparison of the data, some results can be drawn. Improving the air velocity in air-outlet duct and the porosity area of air-outlet duct can increase the cooling speed of air, which also improved the homogeneity of temperature distribution on the products surface. The effect of porosity area on products temperature was not obvious, while products temperature was decreased faster with bigger ventilation velocity. Changing the location of holes on the air-outlet duct had little effects on the temperature decrease of air, but the decreasing amplitude was smaller after cooling process when the holes were concentrated in the middle of the air-outlet duct. A test was developed to verify the results from one of the models, and the simulated results were matched well with the test results, in which the average difference rate (MD) and the root mean square error (RMSE) were 5.05% and 5.95% for change of air temperature, respectively, while those were 14.04% and 16.48% for temperature distribution in the container, respectively. The results revealed the rules of air and products cooling in a fresh-keeping container for fruits and vegetables, which provided a certain reference for the design and optimization of fresh-keeping equipments.