基于有限差分法的食品包装材料不稳定性数值模拟

The Numerical Simulation of Instability of Food Packaging Materials Based on Finite Difference Method

基于有限差分方法数值模拟了塑料食品包装材料化学物向食品(模拟物)的迁移及迁移物在食品内的不稳定性。利用数值计算软件Matlab进行数值模拟得出了不同损耗模式下的迁移预测曲线。结果表明,扩散系数D决定了迁移的动力学过程,分配系数K_(PF)表征平衡时化学物在包装材料和食品内的浓度比值,平衡时食品内的化学物浓度随化学物在包装材料内的初始浓度C_(in)的增加而增加。化学迁移物在食品内存在不稳定现象,这将导致实验结果低估其向食品的迁移。利用损耗函数得到了2种不同损耗模式下的迁移预测曲线。

The process of chemicals＇ migration in food package and their instability in food（ simulants） is simulated using finite difference method. The migration prediction curves are achieved using Matlab. The results show that the migration process is determined by diffusion coefficient D while the partition coefficient K_（PF） represents the ratio of migrant concentration in packaging materials to that in foods at equilibrium. The concentration of migrants in foods at equilibrium increased with the increase of its initial concentration in packaging material C_（in）. While migration,the migrants may be unstable,which can result in the underestimate of their quantity. Lost function is used and prediction curves in 2 different lost mode is achieved.