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Flow (q) vs Velocity (v)
D = diameter of pipe (mm)
Specific Gravity (SG) vs Fluid Density (ρF)
Where ρW = 997.8 kg/m3 for water at 15.55°C
Kinematic viscosity (ν) vs dynamic (absolute) viscosity (μ)
ρ = density of the fluid
SG = Specific gravity of the fluid
Pressure (p) vs pressure head (H) (or fluid column height)
Where ρW = 997.8 kg/m3 for water at 15.55°C
SG = Specific gravity of the fluid
Reynolds number (Re)
D = diameter of pipe (mm)
v = velocity of fluid
= kinematic viscosity
Pipe friction loss (ΔHFP)
Darcy-Weisback equation
g = 9.81 m/s2
D = diameter of pipe (mm)
L = length of 100m of pipe
f = friction parameter
Fittings friction loss (ΔHFF)
K = friction coefficient
g = 9.81 m/s2
Friction parameter for laminar flow regime (f)
Re = Reynolds number
Friction parameter for the turbulent flow regime (f)
(Colebrook equation)
ε = pipe roughness (m)
D = hydraulic diameter of pipe
Re = Reynolds number
Friction parameter for the turbulent flow regime (f)
(Swamee & Jain Equation).
ε = pipe roughness (m)
D = hydraulic diameter of pipe
Re = Reynolds number
Net Positive Suction Head Available (NPSHA)
NPSHA = Static head + surface pressure head - the vapour pressure of fluid - the friction losses in the piping, valves and fittings. NPSHA is a function of the system in which the pump operates. It is the excess pressure of the liquid over its vapour pressure as it arrives at the suction end of the pump.
NPSH Required (NPSHR) is a function of the pump design and can be found on pump manufacturer curves. The NPSHR is the positive head required at the pump suction to overcome pressure drops in the pump and maintain the liquid above its vapour pressure. The NPSHR changes with speed and capacity within any particular pump.
For a pump to operate efficiently and not cavitate, NPSHA must be greater than NPSHR.
Mass flow rate of slurry in a liquid medium (M)
q = volumetric flow rate of slurry
Cv = concentration ratio by volume
SGs = specific gravity (solid)
t = tonne of slurry
Concentration ratio by weight of slurry (Cw)
Cw = concentration ratio by volume
SGs = specific gravity (solid)
SGM = specific gravity (slurry)
Specific gravity of slurry (SGm)
SGL = specific gravity (liquid)
SGs = specific gravity (solid)
Cv = concentration ratio by volume
Mass flow rate of a pulp suspension (M)
t = tonne of pulp suspension
q = volumetric flow rate of pulp
Cv = concentration ratio by volume
