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无线电频率干燥行为在多孔介质:土豆立方体的案例研究与计算机建模
Xiangqing Chen1,2, Yu Liu1,2, Ruyi Zhang1,2
1College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China.
Foods (Basel, Switzerland)
|July 11, 2023
概括
像土豆这样的多孔食物的射频 (RF) 干燥涉及热量和质量转移. 这项研究使用了数值建模来揭示湿度分布如何影响射频干燥效率.
科学领域:
- 食品工程 食品工程
- 热量和质量转移是热量和质量转移.
- 无线电频率处理处理
背景情况:
- 了解热量和质量转移对于优化食品干燥过程至关重要.
- 射频 (RF) 干燥提供了高效和均加热多孔食品材料的潜力.
- 在射频干燥中,热量和质量转移之间的合效应需要详细研究.
研究的目的:
- 为了研究在无线电频率 (RF) 干燥多孔食品材料期间的热量和质量转移的机制.
- 在射频干燥过程中探索湿度分布对温度和水蒸气度模式的影响.
- 为分析和优化射频干燥过程提供一种有效的方法.
主要方法:
- 使用 27.12 MHz 系统对土豆立方体进行 RF 干燥的实验.
- 使用COMSOL Multiphysics®和有限元法来模拟热量和质量转移的数值模型的开发.
- 对模拟结果与温度历史和加热模式的实验数据的验证.
主要成果:
- 模拟结果与实验数据一致,验证了数值模型.
- 观察到不均的水度,与边缘相比,核心的水度更高.
- 温度和水蒸气度分布与水分布相对应,受水分依赖的介电性质的影响.
结论:
- 该研究阐明了热量和质量转移机制在多孔介质的射频干燥中的复杂相互作用.
- 湿度分布显著影响温度和水蒸气度,影响整体干燥过程.
- 开发的数值方法为分析和优化射频干燥技术提供了有价值的工具.
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