Research On Sound Presure Analytical Model Of Graphene Sounder

Graphene sounder is a new device that has emerged in recent years to replace traditional electroacoustic speakers.Graphene sounders do not require vibration components.Compared with traditional speakers that rely on metal vibration components,they avoid the disadvantages of large size,high weight,and limited bandwidth.Graphene sounders have begun to be used in earphones,artificial throats and other fields,but there is a lack of theoretical models for the thermoacoustic effects of graphene sounders,especially for the analysis of the thermal acoustic efficiency of graphene sounders under different excitation conditions.Therefore,in this work,the analysis of sound pressure analytical model of graphene sounder is carried out in order to solve the problems above.The main research contents of this work are as follows:(1)The background of the emergence of graphene sounders is introduced in the first part,and the current research status at home and abroad by classifying two main methods for preparing graphene films: CVD and laser scribing is also included.The advantages of graphene sounders compared to traditional electroacoustic devices are summarized.The advantages and disadvantages between the two preparation methods are also compared.It is found that there is a currently lack of sound pressure theory suitable for graphene sounders under different excitation conditions model.(2)The second part is the thermoacoustic theory of graphene sounders.First,the temperature gradient theoretical model of graphene sounders is introduced,and the temperature gradient equation is re-optimized and solved.Then for the(AC and DC)excitation and pure AC excitation conditions,the sound pressure analytical model of the graphene sounder is derived.Finally,mathematical simulation tools and finite element simulations are used to analyze the factors affecting the thermal acoustic efficiency of graphene sounders.Studies show that the applied(AC and DC)/ pure AC excitation power is directly proportional to the sound pressure level(SPL)of the graphene sounder;there is a 3/2 power relationship between sound pressure level and frequency,which does not change with time in the range of 0-25 k Hz;The sound pressure level is inversely proportional to the measured distance in the far-field range of the graphene sounder with a fixed parameter.(3)In the third part,a graphene sounder is designed using laser scribing technology and the material properties of the laser scribing graphene film are analyzed.The temperature gradient test under(AC and DC)excitation and pure AC excitation is performed,and compared with the theoretical model of temperature gradient in Chapter 2.The linear relationship between the DC voltage component with the temperature gradient under(AC and DC)excitation and the square relationship between the AC voltage with temperature gradient under pure AC excitation are verified respectively.The sound pressure values of graphene sounders are tested under 5V(AC and DC)excitation and 10 V pure AC excitation,compared with the sound pressure analytical model.For the inference that the graphene sounder with a higher(AC and DC)voltage product when the sum of the amplitudes of the applied AC and DC excitations are the same,and the conclusion that the higher the AC voltage value under pure AC excitation,the higher the sound pressure of the graphene sounder,experimental verification is performed.