list basic equations
note that links to basic equations from other pages should pop up in new window
be sure to provide link from Simple Theory to Nomenclature
Nomenclature
A Area
Af Face area
b Balance ratio
bm Fraction of seal face area in mechanical contact
Cp Specific heat
cG Correlation coefficient for parallel sliding load support
Di Inside face diameter
Dm Mean face diameter
Do Outside face diameter
F Force
Fi Flashing Index
Seal duty parameter (dimensionless)
H Hardness (in wear equations)
H Heat generation
K Wear coefficient
k Pressure gradient factor (dimensionless)
L Characteristic length
m mass leakage rate or mass flow rate
N Rotational speed, rpm
P Pressure
P Differential pressure
Psp Unit spring load
Pf Unit face load
Pp Average hydrodynamic face pressure from parallel sliding effects
Pm Average mechanical contact pressure on seal face
Pv vapor pressure
PV Face load times speed
Q volumetric flow rate
r radius
R Radius
Ideal gas constant
s specific gravity
T Torque
T Temperature
V Speed
W load
w Face width
Thermal conductivity
µ Viscosity
density
Leakage coefficient for contact load
Leakage coefficient for materials
Rotational speed, radians/second
subscripts
1 state point 1 (often at OD of seal face)
2 state point 2 (often at ID of seal face)
c closing
l liquid
m mechanical contact
m mean
o opening
t theoretical
v vapor
superscripts
* indicates flashing condition (change of liquid to gas)