B: air water content under temperature and humidity conditions at initial packaging (g /m3 g/m3)

M: weight of packaging auxiliary materials containing water in the package (kg kg)

C: water content of water-containing packaging accessories (g/kg g/kg)

A: surface area of barrier package (m2)

E: correction coefficient under the condition of target humidity

WDD: water vapor transmission rate of barrier packaging (g/m2.day g/m2.d)

T: days of storage and transportation (days d)

Description of a calculation case of desiccant consumption application case

Auto parts produced by an auto parts company are placed in a cubic package with a surface area of 6 square meters. The LDPE barrier bag with water vapor permeability of 0.9g/m2/day (23℃,85%,0. Imm thickness) was sealed and packaged. The product needs to be stored safely in an environment with relative humidity below 50%; The storage time is 25 days and the transportation time is 15 days, so it can only be used after a total of 40 days; When the product is packaged, the ambient temperature is 25℃ and the ambient humidity is 80% relative humidity. In this sealed package, there are also 3 kilograms of wood with water content of 30%0 as buffering auxiliary materials.