Electrical Analogy for Cavitation Erosion Test Results

Electrical systems are analogous to many systems such as acoustic, fluidic, hydraulic, mechanic, magnetic, optic, pneumatic, and thermal systems. As such, electrical systems are applied to study the response of the latter systems to various inputs. A similar analogy is valid between electrical circuits and cavitation erosion systems. The adequate circuit for this purpose is the RC circuit, comprising of a power source, a resistor, and a capacitor. In the cumulative erosion-time curves, obtained by all reviewed cavitation erosion test methods, the erosion rate varies with time. In long-term tests, this rate approaches a constant value asymptotically. This curve was very similar to that obtained during charging and discharging of a capacitor in a RC circuit and was the basis for the analogy between these phenomena. The electrical analogy for cavitation erosion enabled: (a) definition of the cavitation erosion process by a first-order differential equation with three parameters; (b) long-term prediction of erosion values based on short-term tests; (c) comparison of materials and cavitation erosion test methods; and (d) simplification of cavitation erosion standards.