Page 26 - Air pollution and greenhouse gases from basic concepts to engineering applications for air emission control

Nomenclature xxvii

Adsorption wave propagation speed (m/s)
V az
Terminal precipitating velocity of ESP (m/s)
V E

V Average voltage on the inner collector rod (V)
w Water vapor mass fraction in the air (kg vapor/kg air)
w Humidity ratio of air (–)
w Specific humidity of air (–)
Moisture content of the air exiting the room (–)
w e
Moisture content of the supply air (–)
w s
_ w Moisture production rate in the room (kg/s)
W Weight of the adsorbent packed (kg)
W Work done by the system on the surroundings (J)
x Mole ratio in the bulk liquid phase (–)
Critical distance for maximum plume rise (m)
x c
3
The equilibrium concentration of gas i in the liquid phase (mol/m )
x i
x F Remaining mass fraction of the solid fuel (–)
*
x Hypothetical mole fraction corresponding to x in the bulk fluid (–)
X Mole ratio of pollutant to the corresponding liquid (–)
X * Hypothetical or equilibrium mole ratio in gas (–)
y Mole fraction of the target gas at gas–liquid interface (–)
Mole fraction at the interface in gas phase (–)
y i
Mole fraction of the target gas in the bulk liquid at steady state (–)
y ss
y * Hypothetical mole fraction corresponding to y in the bulk fluid (–)
Y Mole ratio of pollutant to the corresponding gas (–)
Y Hydrodynamic factor (–)
2
Y * Composite Young’s modulus (N/m )
Y * Hypothetical or equilibrium mole ratio in gas (–)
z Elevation (m)
Surface roughness height (m)
z 0
2
Mobility of the ions (m /V s)
Z e
Mixing height in atmosphere (m)
z mix
Equilibrium distance between the particle and another surface (0.4 nm) (m)
Z e
2
Electrical mobility of a particle (m /V s)
Z p
2
Z p Optimum electrical mobility of a particle (m /V s)
α Solidification of a filter (–)
δ Boundary layer thickness (m)
δ Width of the adsorption wave (m)
Jump distance in analyzing the aerosol coagulation (m)
δ AB
Δh Plume rise (m)
Maximum plume rise (m)
Δh m
Enthalpy of reaction (J/mol)
ΔH R
Δt Time difference (s)
ΔP Pressure drop across the filter (a positive number) (Pa)
ΔU Internal energy in the system (J)
Δx Thickness of the porous media (m)