模壁厚度对大钢锭传热及疏松缩孔影响的数值模拟

为研究模壁厚度对大型钢锭内部传热及疏松缩孔的影响,本文建立了三种不同厚度的锭模,并利用ProCAST软件对72 t钢锭进行了模拟。通过分析热流密度、凝固场和缩孔分布等模拟结果,发现模壁厚度对钢锭底部热流密度影响较小。增大壁厚,在凝固前期钢锭的中上部热流密度较大,凝固末期钢锭中部的热流密度略有减小。增大壁厚会减少钢锭上部疏松、减小冒口中缩孔体积,但钢锭中下部易产生疏松。壁厚对安全距离影响很小。

Numerical Simulation on the Effect of Wall Thickness of Die on Heat Transfer and Shrinkage and Porosities in Large Steel Ingot

In this paper,three kinds of dies with different thickness are established and a 72 t steel ingot is simulated by ProCAST software to study the effect of wall thickness of the die on heat transfer and shrinkage porosity in large sized steel ingot. By analyzing the simulation results of heat flux,solidification field and shrinkage distribution,we find that the wall thickness of die has little effect on heat flux at the bottom of the ingot. Heat flux in the upper part of the ingot increases with the increase of wall thickness in early solidification stage,while in the middle it decreases a little in the final solidification stage. Increasing wall thickness will diminish porosity in the upper part and lessen shrinkage volume in the riser,but it makes the lower part more likely generate porosity. Wall thickness has little effect on safety distance.