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Al-4.5wt.%Cu合金在多孔预制件内的渗流过程,在入口处发生的重熔和渗透前端凝固的现象,致使整个已渗透区域的温度、固相体积分数和溶质浓度的分布不一致。通过推导渗透动力学模型,建立渗流过程的热、质传递方程,并利用相似变换简化模型,迭代确定参数求解数值。计算结果表明,进口合金过热加剧、增大预制件的预热温度和孔隙率使重熔区长度增加,渗透前沿溶质铜浓度相应减小。增大离心转速,重熔区长度、渗透前沿溶质浓度也减小。过高的转速使整个渗透区域的压力明显增大,从而增加了对预制件的强度要求。数值计算出已渗透区域的热、质分布情况,对离心渗流实验研究有一定的指导意义。
The seepage process of Al-4.5wt.% Cu alloy in porous preform, the remelting at the entrance and the solidification of the infiltration front end resulted in inconsistent distribution of temperature, solid volume fraction and solute concentration throughout the infiltrated area. By deriving the infiltration kinetics model, the heat and mass transfer equations of the seepage process are established, and the similarity transformation is used to simplify the model and the parameters are iteratively determined to solve the numerical values. The calculation results show that the overheating of the imported alloy increases, the preheating temperature and porosity of the preform increase, the length of the remelting zone increases, and the concentration of solute copper decreases correspondingly. Increasing the centrifugal speed, remelting zone length, penetration front solute concentration also decreases. Excessive rotational speed significantly increases the pressure throughout the infiltration area, increasing the strength requirements for the preform. The numerical calculation of the heat and mass distribution in the infiltrated area has some guiding significance for the experimental study of centrifugal seepage.