摘要
将电介质的复介电常数与其静介电参数、交变电场频率的关系引入Maxwell-Wagner非均质电介质理论,建立湿蒸汽等效复介电常数模型,得到饱和水、干饱和蒸汽和湿蒸汽的复介电常数随波长和温度的变化。饱和水复介电常数的实部随波长增加、温度降低而变大,当波长较大时,实部趋于静介电常数,当波长较小时,实部趋于常数,与温度无关;其虚部随波长增加先变大后减小,随温度降低而变大,当波长较小或较大时,虚部趋于0。干饱和蒸汽复介电常数的实部随波长增加、温度升高而变大,当波长较小或温度较低时,实部趋于1;其虚部随波长增加先变大后减小,随温度升高而变大,当波长较小或较大或温度较低时,虚部趋于0。湿蒸汽的复介电常数和干饱和蒸汽规律相近,当湿度增加时,实部和虚部均变大,而且温度越高,数值越大。
The relationship between complex permittivity and static dielectric parameters,frequency of alternating electric field was substituted into the Maxwell-Wagner non-homogeneous dielectric theory.An equivalent complex permittivity model of wet steam was established.The complex permittivity distribution of saturated water,dry saturated steam and wet steam with wavelength and temperature changing were obtained.The real part of saturated water complex permittivity increases with wavelength increasing and temperature decreasing.When wavelength is large,the real part closes to static dielectric constant,and when wavelength is small,it closes to a constant,independent of temperature.The imaginary part of saturated water complex permittivity first increases and then decreases with wavelength increasing,and it increases with temperature decreasing.When wavelength is large or small,the imaginary part closes to 0.The real part of dry saturated steam complex permittivity increases with wavelength and temperature increasing.When wavelength is small or temperature is low,the real part closes to 1.The imaginary part of dry saturated steam complex permittivity first increases and then decreases with wavelength increasing,and it increases with temperature increasing.When wavelength is large or small or temperature is low,the imaginary part closes to 0.The complex permittivity of wet steam is similar to the one of dry saturated steam.When humidity increases especially in high temperature,the real and imaginary parts are larger.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2011年第32期100-106,共7页
Proceedings of the CSEE
基金
国家自然科学基金项目(50676031
51076044)
中央高校基本科研业务费项目(09MG35)~~
关键词
汽轮机
湿蒸汽
湿度测量
复介电常数
微波谐振腔
turbine
wet steam
humidity measurement
complex permittivity
microwave cavity
