The point which shifts to the Decreasing drying period from the Constant drying period is called the Critical moisture content Wc.
The moisture content in which dryness does not advance any more is called the Equilibrium moisture content We.
In a general drying condition, the water (liquid) which can actually carry out evaporation removal is to the Equilibrium moisture content We.
The rate of the water (liquid) which can carry out evaporation removal to the Equilibrium moisture content We is called the Free moisture content Wf.
Wf = Free moisture content
Wi = Initial moisture content
We = Equilibrium moisture content
Wf = Wi - We
By the way, as shown in “1-1. What is drying.” in the strict sense, the moisture content W is different depending on the location in the interior of the wet material.
Expressed correctly, it become the following expressions of relations.