微波频段下麦麸介电特性的测量与分析  

Measurement and Analysis of Dielectric Properties of Wheat Bran at Microwave Frequency

作　　者：王豪 方兵[1] 叶大鹏[1] 谢立敏[1] WANG Hao;FANG Bing;YE Dapeng;XIE Limin(College of Mechanical and Electrical Engineering,Fujian Agriculture and Forest University,Fuzhou 350002,China)

机构地区：[1]福建农林大学机电工程学院,福州350002

出　　处：《中国农业科技导报》2024年第12期115-121,共7页Journal of Agricultural Science and Technology

基　　金：福建省科技计划重大专项(2021N5004)。

摘　　要：介电特性对于麦麸的微波消杀与干燥具有重要研究价值,为探究麦麸的介电特性,在频率0.5~4.0 GHz、含水率1.94%~31.56%、温度35~85℃下,采用同轴传输/反射法测量了麦麸介电常数ε'和损耗因子ε″的变化,并采用多元回归分析法建立了频率为2.45 GHz的ε′、ε″与含水率和温度的数学模型。结果表明:随着频率的增加,ε′和ε″呈单调递增状态;温度越高,ε′和ε″越大;含水率越高,ε′和ε″越大。对模型的验证结果表明,ε′和ε″实验值与计算值之间的决定系数分别为0.99312和0.99082,相对误差分别小于7%和10%,说明该模型可以较好地预测麦麸介电特性。研究结果为麦麸物理性质相似物质的介电特性测量提供指导,对麦麸微波干燥与微波消杀等设备的研发提供理论依据与数据支持。Dielectric properties play important roles in microwave sterilization and drying of wheat bran.In order to explore the dielectric properties of wheat bran,the coaxial transmission/reflection method was used to measure the change of dielectric constant ε′ and loss factor ε″of wheat bran at the frequency of 0.5~4.0 GHz,moisture content of 1.94%~31.56% and temperature of 35~85℃.The mathematical model of ε′ and ε'' with moisture content and temperature of 2.45 GHz was established by multiple regression analysis.The results showed that ε′ and ε″ monotonically increased with the increase of frequency;the higher the temperature was,ε′ and ε″ were larger;the higher the moisture content,ε′ andε″were larger.The verification of the model showed,the determination coefficient between the measured value and the calculated value of the dielectric property was 0.99312 and 0.99082,respectively,and the relative error was less than 7% and 10%,which indicated that the mathematical model can better calculate the dielectric property of wheat bran.The results provided guidance for the measurement of dielectric properties of substances with similar physical properties of wheat bran,and provided theoretical basis and data support for the research and development of microwave drying and microwave killing equipment of wheat bran.

关 键 词：麦麸 传输/反射法 介电特性 微波频段 

分 类 号：S377[农业科学—农产品加工]