In the research group of Prof. Xiaodong Wang, a multiphysics, multiphase numerical model based on the Coulter counting principle demonstrates the ability of micro-particles passing through an aperture in a jet flow of an electrically conducting fluid, relative to an in situ, online, quantitatively technology for the inspection of liquid metal quality. The flow is computed with Eulerian approach, while the particles with Lagrangian one. The color map represents the electromagnetic force density subjecting to a DC current field; the arrows denote the velocity vectors field of the liquid metal flow; the white tubes are the trajectories of non-conducting particles, whose radii are the transient velocity magnitudes of particles, the red balls are the predicted final positions of particles.