Study On Energy Dissipation Mechanism And Vibration Characteristics Of Fluid-Conveying Micro/nano Mechanical Resonators

With the rapid development of microelectromechanical systems(MEMS)and nanoelectromechanical systems(NEMS),these technologies are becoming more and more mature and have been put into practical applications.Nowadays,many MEMS and NEMS devices have been widely used in our daily lives,such as automotive accelerometers and pressure sensors,and fluid-conveying micro-nano tube mechanical resonators are one of the most important applications.In modern industry,the pipeline is the most common kind of current carrying device.With the rapid development of modern science and technology,the pipeline is widely used in many fields such as aerospace engineering,marine engineering,bioengineering,petroleum energy engineering,chemical industry and nuclear industry.Fluid-conveying tube resonators have a large number of applications in the field of micro-nano biological devices and micro-nano electromechanical systems,such as gas storage,liquid storage,liquid delivery and drug delivery systems.In the field of MEMS and NEMS,the electrostatic drive is the preferred driving mode with good structural stability and excellent sensitivity.The thermoelastic damping is the intrinsic energy dissipation mechanism inherent in the micro-nano mechanical devices and is a very important energy consumption at room temperature.Therefore,it is very important to study the vibration characteristics and thermoelastic damping characteristics of the fluid-conveying tube resonators under electrostatic actuation,which is of great significance to the design and manufacture of the fluid-conveying tube resonators.In this paper,the static characteristics,dynamic characteristics and frequency characteristics of the fluid-conveying tube resonators under the action of electrostatic force are analyzed.The thermoelastic damping characteristics of the fluid-conveying tube resonators under different models are also studied.The dynamic model of the fluid-conveying micro beam resonators driven by electrostatic force is deduced and the motion control equation is deduced.The motion control equation is solved by DQM(Differential Quadrature Method).The effects of fringing effects on electrostatic attraction are analyzed and discussed.The effects of various parameters on the static and dynamic characteristics of micro beam are discussed.The Argand diagram of the fluid-conveying micro beam resonator is solved and the influence of various parameters on its stability is analyzed and discussed.The electrostatic attraction characteristics of carbon nanotube resonators are studied,and the influence of midplane streching,non-local effect,electrostatic force and van der Waals force are considered.The static deflection,dynamic characteristics and frequency characteristics of carbon nanotubes were analyzed.The influence of van der Waals force on the electrostatic attraction characteristics of carbon nanotubes was discussed.The thermoelastic damping characteristics of the fluid-conveying tube resonators are investigated.The effects of material properties,crosssectional geometry of the micro beam and the proportion of the micro beam channel on the thermoelastic damping were investigated using four models.Which provides a theoretical reference for the analysis and design of fluidconveying tube resonators.