Design And Thermoelastic Damping Of Microresonator With Bionic Tympanic Membrane

With the rise of bionics,more and more fields have introduced the concept of bionics,or proposed new structures,or achieved functional improvement and perfection,while the field of MEMS can also be combined with bionics.MEMS is the abbreviation of microelectromechanical system.Micromechanical resonators are an important part of the MEMS,and are currently used in a variety of electronic devices.The quality factor is used to evaluate the quality of micro-resonators.It refers to the ratio of the energy of the system itself to the energy lost in the process of vibration.Thermoelastic damping(TED)is an unavoidable way of energy loss in MEMS devices due to the properties of the thermoelastomer itself.Its size has a great impact on the quality factor.Therefore,a microresonant device with bionic tympanic membrane structure is designed and its thermoelastic damping is studied in order to improve the quality factor.Firstly,the existing thermoelastic damping models are summarized,and the derivation process of the thermoelastic damping of micro-beams and micro-plates is sorted out,which provides a reference for the following articles.Then two kinds of bionic tympanic membrane structure models are established based on Bessel function according to the shape characteristics of human ear tympanic membrane.Vibration characteristics are analyzed by Ansys.Then,taking the first kind of tympanic membrane bionic model as an example,the thermoelastic damping expression of tympanic membrane bionic structure is deduced by establishing the coordinate system and combining the stress-strain relationship of plate-shell vibration.In the case of considering only normal heat conduction,the semi-analytical expression of thermoelastic damping can be obtained,which contains the curvature radius term which can not be further processed.Therefore,the specific values of thermoelastic damping of bionic tympanic membrane structure can only be calculated by finite element method,and the effects of height,thickness and radius parameters of bionic tympanic membrane structure on thermoelastic damping are further studied.Finally,the performance comparison between the bionic tympanic membrane structure model and the circular plate with some similar characteristics is made.It is found that the bionic tympanic membrane structure has three main characteristics in transverse vibration: high natural frequency,more in line with the high frequency working environment of the MEMS;concentrated vibration energy,more reasonable distribution,and better resonance effect;under stable high frequency working conditions,less thermal elastic damping and devices.High quality factor.So the bionic structure of tympanic membrane has its unique advantages and practical application value.