Modeling and Simulation of Humidity Inside Sealed Boxes

Taking sealed boxes as the research object, the author analyzes the main source of its moisture content. Based on the permeability mechanism of the sealed boxes and the moisture mechanism of the items inside the boxes, the paper establishes the mathematical model of the relative humidity inside changing over time, applying MATLAB to make a simulation analysis of the mathematical model. The simulation results show that the relative humidity inside the sealed boxes generally varies with the change of the humidity outside; the moisture gradient inside and outside determines the rate of humidity change inside the boxes; as time changes, humidity inside gradually approaches humidity outside. Placing an appropriate amount of desiccating agents in the boxes can effectively reduce the humidity; but in some cases, the desiccating agents slow down not only the increase in the amount of water vapor but also the reduction in the amount of water vapor.