Experiments and computer simulations were conducted to systematically investigate the influence of mashed potato dielectric properties and circulating water electric conductivity on electromagnetic field distribution, heating rate, and heating pattern in packaged food during radio frequency (RF) heating processes in a 6 kW, 27 MHz laboratory scale RF heating system. Both experimental and simulation results indicated that for the selected food (mashed potato) in this study, the heating rate decreased with an increase of electric conductivity of circulating water and food salt content. Simplified analytical calculations were carried out to verify the simulation results, which further indicated that the electric field distribution in the mashed potato samples was also influenced by their dielectric properties and the electric conductivity of the surrounding circulating water. Knowing the influence of water electric conductivity and mashed potato dielectric properties on the heating rate and heating pattern is helpful in optimizing the radio frequency heating process by properly adjusting these factors. The results demonstrate that computer simulation has the ability to demonstrate influence on RF heat pattern caused by the variation of material physical properties and the potential to aid the improvement on construction and modification of RF heating systems.

中文翻译：

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土豆泥介电特性和循环水电导率对27 MHz射频加热的影响

通过实验和计算机模拟，系统地研究了在 6 kW、27 MHz 的射频 (RF) 加热过程中，土豆泥介电特性和循环水电导率对包装食品中电磁场分布、加热速率和加热模式的影响。实验室规模的射频加热系统。实验和模拟结果均表明，对于本研究中选定的食物（土豆泥），加热速率随着循环水电导率和食物含盐量的增加而降低。进行了简化的分析计算以验证模拟结果，这进一步表明，土豆泥样品中的电场分布还受其介电特性和周围循环水的电导率的影响。了解水电导率和土豆泥介电特性对加热速率和加热模式的影响，有助于通过适当调整这些因素来优化射频加热过程。结果表明，计算机模拟能够证明材料物理特性变化对射频加热模式的影响，并有可能帮助改进射频加热系统的构造和修改。了解水电导率和土豆泥介电特性对加热速率和加热模式的影响，有助于通过适当调整这些因素来优化射频加热过程。结果表明，计算机模拟能够证明材料物理特性变化对射频加热模式的影响，并有可能帮助改进射频加热系统的构造和修改。了解水电导率和土豆泥介电特性对加热速率和加热模式的影响，有助于通过适当调整这些因素来优化射频加热过程。结果表明，计算机模拟能够证明材料物理特性变化对射频加热模式的影响，并有可能帮助改进射频加热系统的构造和修改。