Cavitation occurs in a pump when the bulk liquid pressure starts to approach the vapor pressure of the liquid, and cavities of vapor form as seen in Figure 1. This figure shows the inlet of a cavitating pump tested in Concepts NREC’s water flow loop. These cavities can degrade the head rise and efficiency of the pump, create instabilities, and cause significant damage to the pump impeller and other components. To avoid these effects, a pump must operate with an inlet head that is at least as high as the required net positive suction head (NSPH) that the pump was designed to achieve. The NPSH is the difference in the inlet head and the liquid vapor head (or vapor pressure converted to liquid head). Many pumping systems would benefit from the ability to operate at lower NPSH and so reducing the required NPSH of a pump is often of great concern to pump designers.