user's manual for corhyd: an internal diffuser hydraulics model - IfH

Glossary
Table 1: Summary of parameters, Parameters are used with the following major indices: d = diffuser
pipeline section; p = port pipe; j = jet
Parameter Dimension Definition
ρ a kg/m³ average density of ambient water body
ρ e kg/m³ average density of the effluent
A m² pipe cross sectional area
B m equivalent slot width B = A p /l
C c - jet contraction coefficient
D m internal pipe diameter
E m energy head
g’ m/s² reduced gravity, g’ = ∆ρ/ρg
H m head above datum (additional indices: H t = total head at headworks; H d = design
water level elevation of ambient water)
i - numbering of port/riser configurations (counting from seaward end to shore,
starting with 1)
j - numbering of local losses in ports, risers or the diffuser
j 0 m³/s³ buoyancy flux per diffuser length, j 0 =g’q 0
k s m equivalent sand roughness
l m riser spacing
L m length of the considered pipe section
n - total number of local losses j in between one pipe section
N - total number of port/riser locations i of diffuser
N d - total number of diffuser sections (includes feeder)
N g - total number of port/riser groups
N gp - number of risers per group
N p - number of ports per riser
p Pa = N/m² pressure, (additional indices: p l = pressure loss, p a = ambient water pressure)
Q m³/s total flow through outfall system
q m³/s individual discharge through a riser or port at position i
q 0 m²/s mass flux per diffuser length , q 0 = V j B
R m radius of bend
Re - Reynolds number Re = VD/ν
S c - plume centerline dilution
SecNo - diffuser segment number where this group is located in
t s time
V m/s mean flow velocity
x m horizontal coordinate of pipe segment centerline location
y m horizontal coordinate of pipe segment centerline location
z m position or elevation in the vertical
α i - 1 / (number of ports at a riser at position i)
β ° angle of gradual expansion or contraction
ζ - dimensionless loss coefficient for local losses
λ - dimensionless friction coefficient
ν m²/s kinematic viscosity
Institut für Hydromechanik, Universität Karlsruhe 3