Optimization And Application Of Graphene Film Electroacoustic System

Graphene,as a new type of nanometer materials,it has the excellent performance of high mobility,thermal conductivity and mechanical strength,the graphene film loudspeaker based on thermoacoustic theory also arises at the historic moment.Due to the ultra-thin structure of the graphene film,it has the significant advantage in terms of making sound.At the same time,this kind of loudspeaker still has weakness,such as: the sound pressure level is not high enough;“frequency distortion” and so on.So,the graphene film electroacoustic system optimization and application research is of great significance.The mainly work of this paper is as follows:(1)Build the graphene film loudspeaker system,compare different thermoacoustic model and formula,also,analyze the sound field characteristics and influencing factors of graphene films,and test through the experiment.(2)According to the process of electrical energy to thermal energy of the graphene speaker.The theory of the temperature rise of graphene film is introduced.The relationship of graphene film surface temperature oscillation with the input frequency;the relationship of graphene film surface temperature with the input power;and the relationship of graphene film transient temperature with heating time are all analyzed through the experiment.(3)In view of the "frequency distortion" problem of the thermophone.The in-phase operational amplifier circuit is produced in order to solve this problem.At the same time,the method of multifold direct current offset is produced too,combing the newest carbon nanotubes and graphene sound pressure theory,analyzing the ratio of the once frequency sound pressure and the twos.These methods are all used to solve the "frequency distortion" problem the thermophone loudspeaker as far as possible.(4)Use two graphene films to form a graphene film composite system.Then,based on the directivity function and the acoustic interference principle of point source array,we aim to improve the directivity function of the graphene film composite system and make the coupling point sound pressure higher.