Abstract:Studying the features of gas changes in controlled atmosphere compartment contributes to improve performance and promote the application of controlled atmosphere compartment. In order to obtain the changing regulations of oxygen volume fraction in the controlled atmosphere compartment by liquid nitrogen injection, the air infiltration characteristics under thermal pressure of compartment were analyzed, and then the predicting model of oxygen volume fraction in the compartment was established. Moreover, verification experiment was also carried out. Results indicate that during the door-opening, the shorter the door-opening time is, the faster the average temperature rises. The relative humidity quickly rises to 100% within 60s after opening the door on condition that the relative humidity in the compartments is 90%~95%, and the average relative humidity is more than 97% during door-opening. What’s more, the rising velocity of oxygen volume fraction gradually decreases with longer duration of door-opening, and there is certain error between experimental value and theoretical value of oxygen volume fraction based on theoretical calculation and experiment. However, the relative error between the experimental and theoretical value is within 10% when the door-opening time is more than 3min. This research provides a reference for predicting matching amount for liquid nitrogen and safety range of oxygen volume fraction for safe operation.