Experimental investigation of low-frequency pulsed Lorentz force influence on the motion of galinstan melt.
The article presents the results of the numerical and physical experiments, aimed to recognize the influence of pulsed force of electromagnetic field on the melt motion and the fluid velocities. The experiment was performed on the eutectic alloy galinstan in the cylindrical volume, where Ultrasonic Doppler Velocimeter was employed for velocity measurements under conditions of pulsed and steady EM field application. A numerical simulation of the melt flow, forced by the steady forcing, involved a 2D axisymmetric model. The k-ε turbulence model was used to obtain the information about the melt velocities. The verification of the numerical model was carried out for the steady case. The effects of pulsed and steadily applied Lorentz force were compared using the physical experiment. An intensity of the velocity pulsations in galinstan for the pulsed frequencies in the range from 0.05 to 1 Hz considerably exceeded the values, measured in the permanently stirred melt. For higher values of pulsed frequencies (from 1 to 10 Hz) the effect decreases and only slightly differs from the influence of the permanently applied Lorentz force.