The cavitation number of any fluid machinery is defined as $\sigma \frac{\rho -\rho ^{!}}{\rho ^{\frac{V^{2}}{2}}}$ ($\rho$ is absolute pressure, ris density and V is free stream velocity).
The symbolr’ denotes
- Static pressure of fluid
- dynamic pressure of fluid
- Vapour pressure of fluid
- Shear stress of fluid