Page 115 - Industrial Ventilation Design Guidebook
P. 115
80 CHAPTER 4 PHYSICAL FUNDAMENTALS
FIGURE 4.1 Od Mollier diagram for humid air with the perspective modification of Salin-Soininen.
An equation for the water flow vaporizing from the surface of the cloth
can be obtained as
where k is the mass transfer coefficient (m/s). According to the analogy be-
tween heat and mass transfer coefficient,
where the power n varies between 0.33 and 0.5 and
Also,
The dimensionless number Le is called the Lewis number (in Russian literature
it is called the Luikov number). The Lewis number incorporates the specific
3
heat capacity of humid air pc p (J/m °C), the diffusion factor of water vapor in
