Thermo-acoustic theory of graphene films considering heat transfer of substrate materials

Based on the thermo-acoustic theory, a coupled thermal-mechanical model for graphene films is established,and accurate analytical solutions for thermal-acoustic radiation from a graphene thin film is obtained. The sound pressure of the graphene film generator based on different substrates is measured, and the measured values are compared with the theoretical results, the tendency with frequency of experimental results is consistent with the theoretical values,the measured values are slightly lower than the theoretical values. Accuracy of theoretical model is verified. Studies have shown that thermal-acoustic radiation from a graphene thin film has a very wide frequency response. In the low frequency sound pressure level increases with the frequency, the acoustic pressure varies smoothly with frequency In high frequency. Thus it can be used as excellent thermal generator. The thermal effusivity of the substrate is smaller, the sound pressure of grapheme films will be higher. Furthermore, the sound pressure decreases with the increase of heat capacity per unit area of grapheme films. Results will contribute to mechanism research of graphene films generator and its application in the design of loudspeaker and other areas.