摘要:
Freezing is recognized as one of the important technology in food preservation.Considering the change of physical characteristics in beef under the process of the freezing,the equivalent heat capacity method was utilized to process latent heat in phase change,and then the computational fluid dynamics (CFD) numerical simulation technology was applied to simulate the freezing process and establish the differential equations of three dimensional food freezing process.Through the numerical simulation of freezing time,the error between each experimental measuring point (T1,T2,T3,T4 and T5) value and simulation calculation of freezing time were detected to be5.45%,3.9%,5.8%,4.24%,5.8%,respectively,and each point temperature real-time simulation of the average error was 1.79 °C.The results showed that the numerical simulation could predict the beef to freeze time well.%以冰箱冻结牛肉为研究对象,考虑牛肉冻结过程中变物性特点,采用等效热容法处理相变潜热,再用计算流体力学(CFD)数值模拟技术对该冻结过程进行模拟,并建立描述三维食品冻结过程的微分方程,通过数值模拟得出冻结时间的模拟值,各测点(T1、T2、T3、T4、T5)模拟计算的冻结时间与试验冻结时间的误差分别为5.45%,3.90%,5.80%,4.24%,9.60%,各点实时温度的模拟平均误差是1.79°C.结果表明,数值模拟能较好地预测牛肉的冻结时间.