Influence of Drying Temperature on the Different Thermodynamic Parameters during the Indirect Convective Solar Drying of Crocus sativus L. Of Morocco Thin-Layer Solar Drying of Moroccan Saffron

Table 2

Physical data for estimating the CAV value of Crocus sativus L. stigmas.

aw,s: Initial water activity at the surface = 1	1	—
Deff: Effective diffusivity (m^2 s^−1): Hypothesis of 1 ∗ 10^−11 m^2 s^−1	1.00 E^−11	m^2 s^−1
L : Length of stigmas, parallel to air flow (m): 0.3 mm	0.0003	m
: Ambient pressure (Pa): 1.00E + 5 Pa	1.00 E^+05	Pa
: Vapor pressure of airflow (Pa) at about 40°C	7500	Pa
z: Position within the food (m)	1.00 E^−04	m
: Density of vapor (kg·m^−3)	0.69170059	kg·m^−3
: Initial apparent density of water in the material (kg·m^−3)	8.00 E^+02	kg·m^−3
: Diffusivity of water vapor (0.275 cm^2 s^−1)	2.75 E^−05	m^2 s^−1
μ: Dynamic viscosity of the fluid (kg m^−1 s^−1): 1.3 E^−5 Pa s	1.30 E^−05	Pa·s
Thus, CAV (critical airflow velocity) became	2.25 E ^−03	m·s^−1