The development of simple correlation for carbon particles dissolving into liquid metal by using numerical models

Abstract

In this study, a single carbon particle dissolving into liquid metal has been numerically investigated by using a quasi-steady flow model and a transient-dissolution model. The dissolution rate is assumed to be controlled by carbon-mass transfer in liquid metal. It is found that the particle Reynolds number has significant effects on the dissolution rate and distribution on particle surface. If the Reynolds number is low, the highest dissolution rate is at the front stagnation point and monotonically decreases to the rear stagnation point. On the other hand, if the Reynolds number is high, the lowest dissolution rate is close to the flow separation point on particle surface, and the highest and the local highest dissolution rates are respectively at front and rear stagnation points because of the wake formed behind the particle. Furthermore, the shape evolution of dissolving particle at low and high Reynolds numbers are also simulated by using a transient-dissolution model. It is found that the particle body evolves into a self-similar shape during dissolution process. Due to the different dissolution rates and distributions on particle surface, the dissolution time and the shape variation during dissolution process are drastically different. It is found that the particle Reynolds number (the flow agitation) significantly affects particle dissolution. In addition, to simulate a large amount of carbon particles dissolving into liquid metal during steelmaking process, a simple correlation of particle dissolution rates is preliminarily established by using the quasi-steady flow model and further modified according to the numerical results obtained by using the transient-dissolution model.