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Journal of Microwave Power
and Electromagnetic Energy (JMPEE) |
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TITLE |
Influence of Mashed Potato Dielectric Properties and
Circulating Water Electric Conductivity on Radio Frequency Heating [PDF] |
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AUTHORS |
J. Wang,
R. G. Olsen, J. Tang and Z. Tang 2008 42 2 31-46 |
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Abstract 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. Key Words: Computer simulation, dielectric properties, finite element method, numerical modeling, radio frequency heating, radio frequency sterilization, thermal processing |
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