基于计算流体力学技术的橙汁超高温瞬时灭菌工艺优化

分析果汁中常见的细菌，在得出灭菌所需的最低温度(80℃)的基础上，利用FLUENT软件采用二维轴对称模型对橙汁的超高温瞬时灭菌进行模拟计算。对计算流体动力学(CFD)所得优化工艺进行验证实验，误差在9.5%以内，表明CFD对橙汁的超高温灭菌的模拟是可行的。FLUENT模拟得出了不同温度时灭菌的理想时间分别为：135℃(408K)、13s；140℃(413K)、12s；145℃(418K)、12s；150℃(423K)、11s。同时根据卡诺循环，计算超高温瞬时灭菌的机械能耗，135℃(408K)、140℃(413K)、145℃(418K)、150℃(423K)时的单位橙汁的灭菌机械能耗分别为：5856、6550、6709、7953W。根据能耗最低原则，得到了最优化的灭菌工艺为135℃(408K)、13s。

Optimization of UHT Sterilization Process for Orange Juice Based on Computational Fluid Dynamics(CFD)

Common bacteria in orange juice were analyzed to determine the lowest temperature needed for sterilizing orange juice.Simulated calculation of the ultra high temperature(UHT) sterilization of orange juice was performed using FLUENT software with 2 D axisymmetric model.The optimized sterilization process based on computational fluid dynamics(CFD) was validated experimentally with an error under 9.5%,indicating that CFD is applicable to simulate UHT sterilization process of orange juice.The optimal sterilization process required 13 seconds at 135 ℃(408 K),12 seconds at 140 ℃(413 K),12 seconds at 145 ℃(418 K) and 11 seconds at 150℃(423 K).Based on the Carnot cycle efficiency,the consumption of mechanical energy at 408,413,418 K and 423 K was 5856,6550,6709 W and 7953 W,respectively.According to the principle of minimum energy consumption,the optimal sterilization process was sterilization at 135 ℃(408 K) for 13 seconds.