Theory for Heat Transfer in Moist Air
By making the ideal gas assumption in
Equation 4-18
,
The Heat Transfer in Moist Air Interface
solves the following equation:
(4-23)
involving the same variables as in
Theory for Heat Transfer in Fluids
, and the additional
Q
H
term, accounting for the diffusive flux of thermal enthalpy due to the rate of change of air and vapor in moist air. It is defined as (
Ref. 5
):
where:
•
C
p,
v
is the specific heat capacity at constant pressure of vapor (SI unit: J/(kg·K))
•
C
p,
a
is the specific heat capacity at constant pressure of air (SI unit: J/(kg·K))
•
g
w
is the vapor flux by diffusion (SI unit: kg/(m
2
·s))