Coupled electromechanical-hydrodynamic modeling of a low-frequency vibratory cavitator

A compact coupled model is developed for a low-frequency cavitator with two oppositely moving perforated grates. Mechanical oscillations are linked to voltage-driven coil dynamics, variable air gaps, magnetic saturation, nonlinear hydraulic resistance, liquid added mass, and finite-rate vapor-fraction evolution. Simulations for water at 80°C and an absolute chamber pressure of 0.38 MPa cover 41-100 Hz. For the adopted parameter set, the model predicts that the pressure threshold p m i n ≤ p v is crossed over approximately 41-60 Hz. At 50 Hz, the predicted grate amplitude is 2.21 mm, the minimum local pressure is 41.2 kPa, the peak vapor fraction is 4.8 %, and the RMS coil current is 2.81 A. The predicted total electrical input to the two drives is approximately 0.65 kW, while the fundamental dissipative component of the hydrodynamic load corresponds to an equivalent damping of about 138 N·s/m. The calculated phase lags demonstrate that prescribed in-phase harmonic mechanical forcing is inadequate. The model supports preliminary operating-point selection, while its magnetic and hydraulic coefficients require experimental identification. Published experiments on related devices provide technological context; direct validation of the present model and its extension to other fluid rheologies remain future work.