xiv
List of Symbols
or
coefficient in Pfleiderer factor Pf
–
m
dynamic viscosity
Pas
ν
kinematic viscosity
Pas
ξ
pressure loss coefficient
–
ρ
density
kg/m
3
σ
solidity c/s
–
or
Stodola slip factor (3.20)
–
or
cavitation number(8.1)
–
σ a
axial solidity c a /s
–
σ M
moment solidity (3.31)
–
τ
shear stress
N/m
3
or
obstruction factor (Fig. 3.16)
–
φ
flow coefficient v u
a / or v u
r
2
2
/
–
Φ
flow factor (7.4)
–
ψ
work coefficient
2
2
/
W u
D
–
Ψ
head factor (7.5)
–
ψ 0
rotor total pressure coefficient
–
ψ r
rotor static pressure coefficient
–
ω
rotor of relative velocity
m
2
/s
or
enthalpy loss coefficient
–
W
rotational speed
rad/s
s
W
specific speed (7.6)
–
ss
W
suction specific speed (8.14)
–
Subscripts
0
inlet of machine or installation
or
total state
1
just upstream of rotor
1b
just downstream of rotor inlet
2
just downstream of rotor
2b
just upstream of rotor outlet
3
outlet of machine or installation
∞
far away from object
or
with infinite number of blades