1. A modeling method for a fibrous material to be made into a tampon product, the modeling method comprising: analyzing processes and conditions under which the fibrous material is made into the tampon product; determining that moisture, temperature and rate conditions should be tested according to the analysis of the processes and conditions; testing the fibrous material under at least one of moisture, thermal or rate conditions similar to those under which the fibrous material is made into the tampon product to obtain test results; and defining a constitutive model for the fibrous material according to the test results.