Frequency-selected method to improve microwave heating performance

Tang, Zhengming; Hong, Tao; Liao, Yunmao; Chen, Fangyuan; Ye, Jinghua; Zhu, Huacheng; Huang, Kama

doi:10.1016/j.applthermaleng.2017.12.008

Cited by 74 publications

(24 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…By superposition principle the total electric field inside the cavity can be represented by the excitation of two different excitation sources, including the impressed field on the external surface E inc ( r ) and the polarization electric field inside the heating object, namely

bold-italicE ((), r) = E^{inc} ((), r) + j {ωμ}_{0} \int_{V_{d}} \bar{\bar{G_{e}}} ((), bold-italicr bold-italic, bold-italicr') \cdot J_{d} d boldr',

where, μ 0 is permeability of free space,

\bar{\bar{G_{e}}} ((), bold-italicr bold-italic, bold-italicr')

is dyadic Green's function of the empty cavity, r ' and r represent the source point and field point, respectively. Moreover, J d is the polarization volume current density which can be expressed as…”

Section: Mathematical Physics Basis Of Frequency‐selected Microwave Hmentioning

confidence: 99%

“…By superposition principle the total electric field inside the cavity can be represented by the excitation of two different excitation sources, including the impressed field on the external surface E inc (r) and the polarization electric field inside the heating object, 9 namely…”

Section: Dependence Of Microwave Frequency On Heating Uniformitymentioning

confidence: 99%

“…However, the frequency of variable frequency method usually lacks of particular selection, which may waste lots of energy as well as limit the heating efficiency. Recently, a new method named frequency‐selected microwave heating was proposed by us, this method works with selected frequencies and it is much more effective to improve heating performance …”

Section: Introductionmentioning

confidence: 99%

“…Recently, a new method named frequency-selected microwave heating was proposed by us, this method works with selected frequencies and it is much more effective to improve heating performance. 9 In this article, to detailedly demonstrate frequencyselected microwave heating, systematical mathematic derivations regarding the stability of electric field equation, the relation between frequency and heating efficiency, as well as the theory of electromagnetic wave propagation in a multimode cavity are used to interpret its basis in mathematical physics. Then, the characteristics of this method are further deduced and concluded.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Frequency‐selected microwave heating: Its mathematical physics basis and characteristics

Tang

Zhang

Hong

et al. 2020

Int J RF Microw Comput Aided Eng

Self Cite

View full text Add to dashboard Cite

Microwave energy is widely used for heating, however, it usually causes nonuniformity temperatures. In this study, systematical mathematic derivations as well as the theory of electromagnetic wave propagation in a multimode cavity is used to demonstrate the mathematical physics basis of frequency‐selected microwave heating, moreover, the characteristics including the dependence of frequency selecting criteria and the shape of heated samples on heating performance are further analyzed. Finally, numerical computation based on finite element method is used to verify the correctness of the conclusions. This study can help us make better use of microwave energy.

show abstract

bold-italicE ((), r) = E^{inc} ((), r) + j {ωμ}_{0} \int_{V_{d}} \bar{\bar{G_{e}}} ((), bold-italicr bold-italic, bold-italicr') \cdot J_{d} d boldr',

where, μ 0 is permeability of free space,

\bar{\bar{G_{e}}} ((), bold-italicr bold-italic, bold-italicr')

Section: Mathematical Physics Basis Of Frequency‐selected Microwave Hmentioning

confidence: 99%

“…By superposition principle the total electric field inside the cavity can be represented by the excitation of two different excitation sources, including the impressed field on the external surface E inc (r) and the polarization electric field inside the heating object, 9 namely…”

Section: Dependence Of Microwave Frequency On Heating Uniformitymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Frequency‐selected microwave heating: Its mathematical physics basis and characteristics

Tang

Zhang

Hong

et al. 2020

Int J RF Microw Comput Aided Eng

Self Cite

View full text Add to dashboard Cite

show abstract

“…Microwave heating has been widely used in many fields in the past few decades, including food processing, chemical engineering, medical health, and even graphene production [1][2][3][4]. Compared with traditional heating methods, it has numerous advantages like selective energy absorption, high-speed startup, high energy efficiency, and volumetric heating [5][6][7]. However, uneven heating, mainly caused by the mixed modes of the microwave cavity, is still one of the major drawbacks, which hinders the widespread applications of microwave heating in various fields [8].…”

Section: Introductionmentioning

confidence: 99%

A Fast and Accurate Method for Computing the Microwave Heating of Moving Objects

et al. 2020

View full text Add to dashboard Cite

In this paper, we show a fast and accurate numerical method for simulating the microwave heating of moving objects, which is still a challenge because of its complicated mathematical model simultaneously coupling electromagnetic field, thermal field, and temperature-dependent moving objects. By contrast with most discrete methods whose dielectric parameters of the heated samples are updated only when they move to a new position or even turn a circle, in our simulations a real-time procedure is added to renew the parameters during the whole heating process. Furthermore, to avoid the mesh-mismatch induced by remeshing the moving objects, we move the cavity instead of samples. To verify the efficiency and accuracy, we compared our method with the arbitrary Lagrangian–Eulerian method, one of the most accurate methods for computing this process until now. For the same computation model, our method helps in decreasing the computing time by about 90% with almost the same accuracy. Moreover, the influence of the rotational speed on the microwave heating is systematically investigated by using this method. The results show the widely used speed in domestic microwave ovens, 5 rpm, is indeed a good choice for improving the temperature uniformity with high energy efficiency.

show abstract

Dynamic model for controlled uniform processing under microwave heating by using a heat exchanger

Teng

Shu

Hong

et al. 2021

Int J RF Microw Comput Aided Eng

Self Cite

View full text Add to dashboard Cite

The development of microwave heating technology promotes the improvement of industry quality and efficiency, but the drawbacks of microwave heating, such as uneven heating, prevent its wide application in industry. In this paper, a double-layer ring tube is proposed for improving the heating uniformity and achieving the target temperature. The gap between the inner and outer tubes is evenly divided into four regions, and the cooling liquid flows through the gap to control the temperature of the heating target placed in the inner tube. Maxwell's equation, heat conduction equation, Navier-Stokes equation and the mass conservation equation are coupled to simulate the heating process, and the experimental data and simulation data are compared to verify the correctness of the model. Meanwhile, the heating uniformity of structure with or without heating exchanger is compared, and the effect of different fluid velocities, different sizes of the reactor and different dielectric constant of heating target on the heating performance is discussed.

show abstract

Frequency-selected method to improve microwave heating performance

Cited by 74 publications

References 26 publications

Frequency‐selected microwave heating: Its mathematical physics basis and characteristics

Frequency‐selected microwave heating: Its mathematical physics basis and characteristics

A Fast and Accurate Method for Computing the Microwave Heating of Moving Objects

Dynamic model for controlled uniform processing under microwave heating by using a heat exchanger

Contact Info

Product

Resources

About