کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
10620910 988741 2006 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Specific heat, polarization and heat conduction in microwave heating systems: A nonequilibrium thermodynamic point of view
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Specific heat, polarization and heat conduction in microwave heating systems: A nonequilibrium thermodynamic point of view
چکیده انگلیسی
A microwave (MW) field can induce in a dielectric material an oscillatory polarization. By this mechanism part of the energy carried by the waves is converted into chaotic agitation, and the material heats up. MW heating is a nonequilibrium phenomenon, while conventional heating can generally be considered as quasi-static. Excess (or nonthermal) effects of MWs with respect to conventional heating lie in this difference. Macroscopically, MW heating can be described in the framework of linear nonequilibrium thermodynamics (NET). This approach indicates that in a dielectric material under MW heating the specific heat has a dynamic component linked to the variation of polarization with temperature, and that polarization and heat conduction are intertwined. In particular, linear NET provides a new phenomenological equation for heat conduction that is composed of the classic Fourier's law and an additional term due to polarization relaxation. This term quantitatively describes the excess effect of MWs on thermal conduction.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 54, Issue 7, April 2006, Pages 1843-1849
نویسندگان
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