Mechanisms of Suspended Microparticle Clogging in Constricted Channels: Insights From a Lattice Boltzmann‐Discrete Element Simulation

Abstract The migration‐clogging‐sealing process of microparticle suspensions in constricted channels is highly relevant to geotechnical, hydraulic, and environmental engineering. In this study, a coupled lattice Boltzmann‐discrete element method is employed, incorporating dense‐particle corrections into the classical partially saturated method and integrating DLVO (Derjaguin‐Landau‐Verwey‐Overbeek) interactions into the contact model. This approach enables high‐precision simulation of suspended microparticle motion in electrolyte solutions. A systematic analysis of particle properties, flow field characteristics, and channel geometry shows that the sealing mechanism is jointly controlled by the Archimedes and Stokes numbers and can be classified as either deposition‐dominated or collision‐dominated. Under high‐velocity conditions, clogging is more likely triggered by mechanical bridging resulting from particle collisions. Switching the injection method from volume (constant discharge) control to pressure (hydraulic head gradient) control reduces the continuous erosion of particles after sealing. With respect to geometry, the constriction angle and the width of the narrow section are the key parameters affecting clogging, while channel height also plays a significant role when it is less than roughly 10 times the particle diameter. Based on these factors, a dimensionless index J is proposed to evaluate the ease of suspended particle transport. The results indicate that as J increases, the particle transport state sequentially transitions from continuous flow (particles can pass through the channel freely) to continuous erosion (particle deposition is in equilibrium with deposited particle mobilization), to intermittent flow (particles alternately accumulate and remobilize at the constriction), and finally to sealing (clogging prevents subsequent particle migration).