Numerical simulation of coexisting solid-liquid slag trickle flow in a coke bed by the sph method with a non-Newtonian fluid model

A simulation of the dripping behavior of solid-phase suspended molten slag in a coke bed was performed using the Bingham fluid model in the framework of smoothed particle hydrodynamics (SPH). SPH can track the motion of droplets which are suspended in dispersed solids. A case study was performed in which the yield coefficient varied with the viscosity coefficient of the molten SiO₂-CaO-Al₂O₃ slag, with suspended solids approximated by the Bingham fluid model, and the holdup droplets were trapped at approximately the same site regardless of the yield value. When the yield value exceeded the threshold, the volume of each holdup droplet increased. This threshold is correlated with the decrease in the shear rate at the bottleneck. Increasing the solid phase ratio in the molten slag is also predicted to increase the yield value with viscosity; thus, the amount of holdup droplets increases at the specific holdup sites as a dispersed phase. This indicates that the increase in the yield value approaches the powder holdup mechanism that is closed one after another starting from a specific holdup site.