Is more airflow always beneficial in drying processes?

The rationale behind the choice indicating that more airflow is not always beneficial in the drying process centers on the potential for premature drying at the surfaces of materials. While increased airflow can enhance evaporation and drying rates, it can also lead to a condition known as "case hardening," particularly with porous materials.

In cases where the outer layer of a substrate dries too quickly, it can form a hard shell or barrier, preventing moisture trapped within from escaping. This can result in uneven drying and potential structural damage, such as warping or cracking. Moreover, in an environment where sufficient moisture is still present deeper in the materials, excessive airflow can exacerbate these issues.

Proper airflow is critical, but it must be balanced with humidity levels and the moisture content of the materials being dried. This balance ensures that drying occurs uniformly without causing damage to the materials involved.