凝固过程微观数值模拟中的碰撞因子

THE REASONABLE MODEL OF CORRECTION COEFFICIENT OF GRAIN IMPINGEMENT IN MICROMODELING OF SOLIDIFICATION PROCESS

通过数值计算与实验相结合的方法，对凝固过程微观数值模拟中碰撞因子的已有形式进行了分析、比较．在此基础上，提出了在固相体积分数（ｆｓ）大于π／６后采用阻［１－（ｆｓ－π／６）］４作为反映晶粒接触因素的碰撞因子是一种更合理的形式．经实验验证，在该形式下的模拟结果更接近于实际．

Based on the comparison and analysis of the two kinds of models treating grain impingement, a formula [1 - (fs - π/6)]4 was proposed as a correction coefficient to reflect impingement when the solid volume fraction (fs) is greater than π/6. The cooling curve simulated by using the above correction coefficient approximates more to the experimental result than Other models.