Cavitation Number
The Cavitation Number or Cavitation Parameter is a "special edition" of the dimensionless Euler Number.
- The Euler Number - an introduction to and a definition of the Euler Number
The Cavitation Number is useful when analyzing fluid flow dynamics problems where cavitation may occur.
The Cavitation Number can be expressed as
σ = (pr - pv) / (1/2 ρ v2) (1)
where
σ = Cavitation number
pr = reference pressure (Pa)
pv = vapor pressure of the fluid (Pa)
ρ = density of the fluid (kg/m3)
v = velocity of fluid (m/s)
To prevent cavitation
- avoid low pressure - pressurize supply tanks if necessary
- reduce fluid temperature
- use larger suction pipe diameters - reduce minor losses
- use cavitation resistant materials or coatings
- small amounts of air supplied to the suction system may reduce the amount of cavitation damage
- keep available NPSH well above required NPSH.
Related Topics
• Fluid Mechanics
The study of fluids - liquids and gases. Involving velocity, pressure, density and temperature as functions of space and time.
Related Documents
Cavitation
Cavitation occurs in fluid flow systems where the local static pressures are below the fluids vapor pressure.
Control Valves - Cavitation
Control valves and cavitation, application ratio and multi stage control valves.
Euler Number
Introduction to the Euler Number used in fluid mechanics.