LF精炼工艺中钢包底吹氩过程数值模拟

Numerical Simulation of Ladle Bottom Argon Purging in the LF Refining Process

精炼过程中进行钢包吹氩是一种去除钢中夹杂,提升其洁净度的重要手段。为快速且低成本地捕获最佳吹氩流量,通过流体分析软件FLUENT对钢包偏心底吹氩过程进行数值模拟。结果表明:在合适的吹气量下,气流会随着吹气时间的延长,在钢液中形成一个闭合的循环区域;吹气量从10 Nm^(3)/h增大到30 Nm^(3)/h,气流的平均动能和平均速度显著增大,死区比例则从21%下降到6%;当吹气量超过临界值30 Nm^(3)/h时,进一步加大吹气量,死区比例趋于稳定,氩气利用率降低;吹气量为30 Nm^(3)/h时达到最佳吹气量,此时钢液中的流体能够获得较大的平均湍动能和平均速度,且钢液中死区比例也达到最小,钢液获得较大的搅拌强度和搅拌区域。

By removing the inclusion in molten steel, the ladle bottom argon purging in LF refining process is an important method for improving the cleanliness of steel. In this paper, in order to quickly and low cost get the optimized blowing argon flow rate,the numerical simulation of argon bottom blowing was carried out by using fluid analysis software FLUENT. The results show that the gas flow would forme a closed circulation area at the appropriate blowing argon flow rate. With the blowing argon flow rate increasing from 10 Nm^(3)/h to 30 Nm^(3)/h, the average turbulent kinetic energy and the average argon flow velocity improve significantly, and the stagnation zone volume rate in steel drops from 21% to 6%. Further increasing the blowing argon flow rate beyond the key value of 30 Nm^(3)/h, the stagnation zone volume rate doesn’t change obviously, but the utilization rate of argon gas would decrease. The results suggest that the optimized blowing argon flow rate is 30 Nm^(3)/h, in which the steel liquid has a large agitation strength and stirring area with the maximum fluidity average turbulent kinetic energy, the fastest average argon flow velocity and the smallest stagnation zone volume rate.