微波干燥过程中氯化钠电磁特性数值模拟研究
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摘要
多模微波腔体是最为常见的加热腔体,然而在加热过程中待加热的物料常会表现出选择性加热的特点,这是由于微波加热的效果与物料的电磁特性参数密切相关。针对氯化钠在微波腔体中加热效果呈现出的差异性造成腔体内电磁场分布以及加热不均匀等问题,建立电磁热模型对氯化钠在加热过程中的电磁敏感性对温度变化的影响进行研究。通过时域有限差分法(Finite Difference Time Domain,FDTD)耦合求解电磁场及热场方程,对微波加热氯化钠的升温速率随着电磁特性参数以及氯化钠含水率变化的规律进行实时的仿真计算。结果表明:随着氯化钠相对介电常数的增大,其腔体内的电场分布越均匀,介质对电磁波的吸附作用越明显。随着氯化钠损耗角和含水率的增大,腔体内氯化钠的升温速率以及稳态温度增大。
The multimode resonant cavity is the most common heating cavity. The materials often show selective heating performance during the heating process due to the effect of microwave heating having a closely relationship with the parameters of electromagnetism. As the heating effect of sodium chloride in the microwave cavity results in electromagnetic distribution and uneven heating in the cavity, the electromagnetic-thermal field model is established to study the sensitivity of electromagnetic heating sodium chloride in the heating process. The electromagnetic field and thermal field equations are coupled by the method of finite difference time domain method(FDTD). The heating rate of microwave heating sodium chloride is simulated in real time with the electromagnetic characteristic parameters and the change of moisture content of sodium chloride. The results show that with the increase of relative dielectric constant of sodium chloride, the distribution of electric field in the cavity is more uniform and the absorption of electromagnetic wave by the medium is more obvious. With the increase of sodium chloride loss angle and moisture content, the temperature rise rate and the steady-state temperature of sodium chloride in the cavity increase.
The multimode resonant cavity is the most common heating cavity. The materials often show selective heating performance during the heating process due to the effect of microwave heating having a closely relationship with the parameters of electromagnetism. As the heating effect of sodium chloride in the microwave cavity results in electromagnetic distribution and uneven heating in the cavity, the electromagnetic-thermal field model is established to study the sensitivity of electromagnetic heating sodium chloride in the heating process. The electromagnetic field and thermal field equations are coupled by the method of finite difference time domain method(FDTD). The heating rate of microwave heating sodium chloride is simulated in real time with the electromagnetic characteristic parameters and the change of moisture content of sodium chloride. The results show that with the increase of relative dielectric constant of sodium chloride, the distribution of electric field in the cavity is more uniform and the absorption of electromagnetic wave by the medium is more obvious. With the increase of sodium chloride loss angle and moisture content, the temperature rise rate and the steady-state temperature of sodium chloride in the cavity increase.
引文
[1] 王文祥.微波工程技术[M].北京:国防工业出版社,2009.1-5 Wang W X.Microwave engineering technology[M].Beijing:National Defense Industry Press,2009.1-5
[2] 李解,张邦文,李保卫.白云鄂博中贫氧化矿微波磁化焙烧-磁选试验研究[J].金属矿山,2010,407(5):89-91 Li J,Zhang B W,Li B W.Experimental study on process of microwave magnetizing roast plus magnetic separation for medium-low grade oxidized ores containing hematite of Bayanobo [J].Metal Mine,2010,407(5):89-91
[3] 唐莹.微波加热CaO-SiO2体系材料的数值模似研究[D].武汉:武汉理工大学,2007 Tang Y.Numerical modeling study of microwave heating CaO-SiO2 system materials[D].Wuhan:Wuhan University of Technology,2007
[4] 杨晓庆,黄卡玛.微波与化学反应相互作用中的关键问题讨论[J].电波科学学报,2006,21(5) :802-809 Yang X Q,Huang K M.Investigation of key problems of interaction between microwave and chemical reaction[J].Journal of Radio Science,2006,21(5):802-809
[5] Yugo Tasei,Takuya Yamakami.Mechanism for microwave heating of 1-(4'-cyanophenyl)-4-propylcyclohexane characterized by in situ microwave irradiation NMR spectroscopy[J].Journal of Magnetic Resonance,2015,254:27-34
[6] Radha Raman Mishra,Apurbba Kumar Sharma.Microwave-material interaction phenomena:heating mechanisms,challenges and opportunities in material processing[J].Composites Part A:Applied Science and Manufacturing,2016,81:78-97
[7] 李鹏飞.基于ADI-FDTD的微波加热模型研究[D].成都:电子科技大学,2010 Li P F.Study of microwave heating model based on ADI-FDTD[D].Chengdu:University of Electronic Science and Technology of China,2010
[8] Hong Y D,Lin B Q,Li H,et al.Three-dimensional simulation of microwave heating coal sample with varying parameters[J].Applied Thermal Engineering,2016,93(25) :1145-1154
[9] Zhao X,Huang K M,Yan L P.A preliminary study on numerical simulation of microwave heating process for chemical reaction and discussion of hotspot and thermal runaway phenomenon[J].Physics Mechanics and Astronomy,2009,52(4):551-562
[10] Diogo Batista Oliveira ,Elson Jose Silva ,Rose Mary S Batalha.Decision criterion based on sensitivity analysis to solve microwave heating in a single-mode cavity[J].IET Sci Meas Technol,2014,8(4):178-186
[11] Chen H,Zhang J,Fan Z B,et al.The analysis of parametric sensitivity based on designing and optimization of a new microwave heating system[J].High Temperature Materials and Processes.2017,36(8):847-853
[12] 李鹏飞,谢扩军.微波陶瓷加热的数值模拟[J].材料导报,2009,23(11A):100-102 Li P F,Xie K J .Numerical simulation of microwave sintering of ceramics[J].Materials Herald,2009,23(11A):100-102
[13] 李云峰.微波加热过程中材料的介电性及热特性研究[D].昆明:昆明理工大学,2012 Li Y F.Dielectric properties and thermal properties of materials during microwave heating[D].Kunming:Kunming University of Science and Technology,2012
[14] Peng Z W,Hwang J Y,Park C L,et al.Numerical analysis of heat transfer characteristics in microwave heating of magnetic dielectrics[J].Metallurgical and Materials Transactions A,2012,43(3):1070-1078
[15] 尚小标,陈君若,张伟峰,等.氯化钠在微波干燥中的动态吸波效率研究[J].化学工程,2014,42(8):41-45 Shang X B,Chen J R,Zhang W F,et al.Dynamic absorption efficiency of sodium chloride in microwave drying[J].Chemical Engineering,2014,42(8):41-45
[16] Zhu J,Kuznetsov A V,Sandeep K P.Mathematical modeling of continuous flow microwave heating of liquids (effects of dielectric properties and design parameters)[J].International Journal of Thermal Sciences,2007,46(4):328-341
[17] Catalá-Civera J M,Canós A,Plaza-González P,et al.Dynamic measurement of dielectric properties of materials at high temperature during microwave heating in a dual mode cylindrical cavity[J].IEEE Transactions on Microwave Theory and Techniques,2015,63(9):2905-2914
[18] Torres F,Jecko B.Complete FDTD analysis of microwave heating processes in frequency-dependent and temperature-dependent media[J].IEEE Transactions on Microwave Theory and Techniques,1997,45(1):108
[19] Elsherbeni A,Demir V.MATLAB模拟的电磁学时域有限差分法[M].喻志远,译.北京:国防工业出版社,2013.2-20 Elsherbeni A,Demir V.The finite-difference time-domain method for electromagnetics with MATLAB simulations[M].Yu Z Y,Trans.Beijing:National Defense Industry Press,2013.2-20
[20] Kee K S.Numerical solution of initial boundary value problems involving Maxwell's equations in isotropic media[J].IEEE Transactions on Antennas and Propagation,1966,14(3):302-307
[21] 彭金辉,刘秉国,张利波,等.高温微波冶金反应器的研究现状及发展趋势 [J].中国有色金属学报,2011,21(10):2607-2615 Peng J H,Liu B G,Zhang L B,et al.Research status and trend of high-temperature microwave metallurgy reactor[J].The Chinese Journal of Nonferrous Metals,2011,21(10):2607-2615
[22] Huang K M.New characteristics of oxido-reduction reaction of KI and KMnO4 irradiated by amplitude-modulated electromagnetic waves[J].Chinese Science Bulletin,1996,41(15):1259-1262
[23] 杨儒贵.高等电磁场理论[M].北京:高等教育出版社,2008.457-458 Yang R G.Advanced electromagnetic theory [M].Beijing:Higher Education Press,2008.457-458
[24] 刘晨辉.基于冶金物料介电特性的微波加热应用新工艺研究[D].昆明:昆明理工大学,2014 Liu C H.Study on new technology of microwave heating based on dielectric properties of metallurgical materials[D].Kunming:Kunming University of Science and Technology,2014
[25] Liu C,Zhang L,Peng J,et al.Dielectric properties and microwave heating characteristics of sodium chloride at 2.45 GHz [J].High Temperature Materials and Processes,2013,32(6):517-603
[2] 李解,张邦文,李保卫.白云鄂博中贫氧化矿微波磁化焙烧-磁选试验研究[J].金属矿山,2010,407(5):89-91 Li J,Zhang B W,Li B W.Experimental study on process of microwave magnetizing roast plus magnetic separation for medium-low grade oxidized ores containing hematite of Bayanobo [J].Metal Mine,2010,407(5):89-91
[3] 唐莹.微波加热CaO-SiO2体系材料的数值模似研究[D].武汉:武汉理工大学,2007 Tang Y.Numerical modeling study of microwave heating CaO-SiO2 system materials[D].Wuhan:Wuhan University of Technology,2007
[4] 杨晓庆,黄卡玛.微波与化学反应相互作用中的关键问题讨论[J].电波科学学报,2006,21(5) :802-809 Yang X Q,Huang K M.Investigation of key problems of interaction between microwave and chemical reaction[J].Journal of Radio Science,2006,21(5):802-809
[5] Yugo Tasei,Takuya Yamakami.Mechanism for microwave heating of 1-(4'-cyanophenyl)-4-propylcyclohexane characterized by in situ microwave irradiation NMR spectroscopy[J].Journal of Magnetic Resonance,2015,254:27-34
[6] Radha Raman Mishra,Apurbba Kumar Sharma.Microwave-material interaction phenomena:heating mechanisms,challenges and opportunities in material processing[J].Composites Part A:Applied Science and Manufacturing,2016,81:78-97
[7] 李鹏飞.基于ADI-FDTD的微波加热模型研究[D].成都:电子科技大学,2010 Li P F.Study of microwave heating model based on ADI-FDTD[D].Chengdu:University of Electronic Science and Technology of China,2010
[8] Hong Y D,Lin B Q,Li H,et al.Three-dimensional simulation of microwave heating coal sample with varying parameters[J].Applied Thermal Engineering,2016,93(25) :1145-1154
[9] Zhao X,Huang K M,Yan L P.A preliminary study on numerical simulation of microwave heating process for chemical reaction and discussion of hotspot and thermal runaway phenomenon[J].Physics Mechanics and Astronomy,2009,52(4):551-562
[10] Diogo Batista Oliveira ,Elson Jose Silva ,Rose Mary S Batalha.Decision criterion based on sensitivity analysis to solve microwave heating in a single-mode cavity[J].IET Sci Meas Technol,2014,8(4):178-186
[11] Chen H,Zhang J,Fan Z B,et al.The analysis of parametric sensitivity based on designing and optimization of a new microwave heating system[J].High Temperature Materials and Processes.2017,36(8):847-853
[12] 李鹏飞,谢扩军.微波陶瓷加热的数值模拟[J].材料导报,2009,23(11A):100-102 Li P F,Xie K J .Numerical simulation of microwave sintering of ceramics[J].Materials Herald,2009,23(11A):100-102
[13] 李云峰.微波加热过程中材料的介电性及热特性研究[D].昆明:昆明理工大学,2012 Li Y F.Dielectric properties and thermal properties of materials during microwave heating[D].Kunming:Kunming University of Science and Technology,2012
[14] Peng Z W,Hwang J Y,Park C L,et al.Numerical analysis of heat transfer characteristics in microwave heating of magnetic dielectrics[J].Metallurgical and Materials Transactions A,2012,43(3):1070-1078
[15] 尚小标,陈君若,张伟峰,等.氯化钠在微波干燥中的动态吸波效率研究[J].化学工程,2014,42(8):41-45 Shang X B,Chen J R,Zhang W F,et al.Dynamic absorption efficiency of sodium chloride in microwave drying[J].Chemical Engineering,2014,42(8):41-45
[16] Zhu J,Kuznetsov A V,Sandeep K P.Mathematical modeling of continuous flow microwave heating of liquids (effects of dielectric properties and design parameters)[J].International Journal of Thermal Sciences,2007,46(4):328-341
[17] Catalá-Civera J M,Canós A,Plaza-González P,et al.Dynamic measurement of dielectric properties of materials at high temperature during microwave heating in a dual mode cylindrical cavity[J].IEEE Transactions on Microwave Theory and Techniques,2015,63(9):2905-2914
[18] Torres F,Jecko B.Complete FDTD analysis of microwave heating processes in frequency-dependent and temperature-dependent media[J].IEEE Transactions on Microwave Theory and Techniques,1997,45(1):108
[19] Elsherbeni A,Demir V.MATLAB模拟的电磁学时域有限差分法[M].喻志远,译.北京:国防工业出版社,2013.2-20 Elsherbeni A,Demir V.The finite-difference time-domain method for electromagnetics with MATLAB simulations[M].Yu Z Y,Trans.Beijing:National Defense Industry Press,2013.2-20
[20] Kee K S.Numerical solution of initial boundary value problems involving Maxwell's equations in isotropic media[J].IEEE Transactions on Antennas and Propagation,1966,14(3):302-307
[21] 彭金辉,刘秉国,张利波,等.高温微波冶金反应器的研究现状及发展趋势 [J].中国有色金属学报,2011,21(10):2607-2615 Peng J H,Liu B G,Zhang L B,et al.Research status and trend of high-temperature microwave metallurgy reactor[J].The Chinese Journal of Nonferrous Metals,2011,21(10):2607-2615
[22] Huang K M.New characteristics of oxido-reduction reaction of KI and KMnO4 irradiated by amplitude-modulated electromagnetic waves[J].Chinese Science Bulletin,1996,41(15):1259-1262
[23] 杨儒贵.高等电磁场理论[M].北京:高等教育出版社,2008.457-458 Yang R G.Advanced electromagnetic theory [M].Beijing:Higher Education Press,2008.457-458
[24] 刘晨辉.基于冶金物料介电特性的微波加热应用新工艺研究[D].昆明:昆明理工大学,2014 Liu C H.Study on new technology of microwave heating based on dielectric properties of metallurgical materials[D].Kunming:Kunming University of Science and Technology,2014
[25] Liu C,Zhang L,Peng J,et al.Dielectric properties and microwave heating characteristics of sodium chloride at 2.45 GHz [J].High Temperature Materials and Processes,2013,32(6):517-603