Quantitative Description Of Electromagnetic Energy Density And Possible Applications

Energy conversion and conservation are widespread in nature,and electromagnetic fields are no exception.The transformation,transmission and conservation of electromagnetic energy are the research hotspots in the fields of materials,energy,information,biology,etc.It has been achieved in many aspects such as electromagnetic metamaterials,wireless energy transmission,wireless communication,integrated circuit antenna design,electromagnetic compatibility,electromagnetic biotechnology,etc.Significant progress has been made.This article focuses on the conversion and conservation of electromagnetic energy in lossy media,and has carried out the following work.Firstly,the research background of this paper is introduced:electromagnetic field theory and Poynting theorem;the research and application of metamaterials,especially transmission line metamaterials;and the influence of metamaterials on electromagnetic energy storage and loss properties.Then,the theoretical basis and numerical simulation tools are introduced.In the third part,the common expressions of electromagnetic energy storage and electromagnetic loss energy density are systematically investigated,and the physical meaning and formula derivation of energy storage are carefully discussed,and the self-consistency and correctness of the relevant formulas are further demonstrated.In the fourth part,the energy storage and loss characteristics of electromagnetic wave propagating in two-layer two-dimensional metamaterials based on transmission line are studied by using field method.Then,according to Kirchhoff's law and Joule's law,the energy conversion and conservation formula expressed by circuit parameters and the energy density of storage and loss expressed by circuit parameters,which are similar to Poynting's theorem,are derived The experimental scheme for checking the correctness of loss density is proposed.The fifth part,through the design of transmission line filter,deepen the understanding of the relevant theory.Finally,the paper gives a summary and ideas to improve the research work.