Latin Alphabet
A | Area (m2) |
c |
Concentration - particularly chlorine(mg/l) |
C | C-value for a pipe (Hazen-Williams formula) |
D | Diameter |
ds | Inlet diameter |
dp | Outlet diameter |
dt | Time interval (s) |
e | Specific consumption of electric energy (kWh/m3) |
g |
Acceleration due to gravity (9.80665 m/s2) |
H | Head - elevation of HGL |
HGL | Hydraulic Grade Line |
Hp | Pump head, or 'lift' |
k |
k Chlorine decay rate (day -1) |
K | Unit resistance of a pipe |
k h | Demand/load factor |
L | Length |
Mld | Megalitres per day |
n | Rotational speed of pump (rpm) |
P | Power (usually electric power) (kW) |
p |
p Local pressure (Pa = N/m2) |
Qdem | Water consumption (demand) |
Qlos | Loss of water (usually due to leakage) |
Re | Reynolds number ( = vD / u ) |
S | Valve opening (%) |
t | Time (hh:mm) |
T | Period of time (s) |
v | Flow velocity |
V | Storage/Volume |
x, y, z | Coordinates |
Z | Elevation (of ground, or bottom of a reservoir, etc.) |
Greek Alphabet
χ |
Local (minor) loss coefficient |
η |
Efficiency (%) |
λ |
Friction coefficient (Darcy Weisbach formula) |
υ |
Kinematic viscosity (m2/s) |
ρ |
Density (kg/m2) |
ρ |
Angular velocity (s-1) |
ω |
Phase angle between voltage and current applied to a load. (Cos φ = Power factor) |