Analysis of thermoelastic damping effects on rf mems resonators m. Therefore, the effect of thermoelastic dissipation, and consequently the damping, is most pronounced when the vibration frequency is close to the thermal relaxation frequency. Anthony1 1school of mechanical engineering, university of birmingham corresponding author. Excerpt from the proceedings of the 2014 comsol conference in cambridge air damping simulation of mems torsional paddle n. Estimation of thermoelastic damping of vibrations in micro. Multiphysics modeling of mems devices november 20 executive summary power is increased with dedicated tools. Jan 16, 2015 we have created a video tutorial for those of you who are new to the comsol multiphysics simulation software and need an introduction on how to use it. Request pdf engineering mems resonators with low thermoelastic. Thermoelastic damping depending on vibration modes of nano beam resonator 321 coupled thermoelastic equations. Comsol, the comsol logo, comsol multiphysics, comsol desktop, comsol server, and. Section 2 gives an overview of the basic equations for thermoelasticity, presenting a brief summary of the balance and of the constitutive equations used in the. Comsol lep tutorial for tank flow system two cstr in series. May, 2011 may 2011 finite element modelling and simulation of thermoelastical damping.
Submit a plot similar to figure 52 in the documentation. An investigation on thermoelastic damping of highq ring. Request pdf a finite element analysis of thermoelastic damping in vented mems beam resonators the effect of geometry on thermoelastic damping in microbeam resonators is evaluated using an. The effect of thermoelastic damping on the total qfactor of stateoftheart mems gyroscopes with complex beamlike suspensions. Effect of thermoelastic damping in nonlinear beam model of mems resonators by differential quadrature method july 2015 journal of applied mathematics and computational mechanics. Structure interaction interface of comsol multiphysicstm for estimation of the air damping for a variety of other mems devices, the experimental and simulated performance of. Following the steps given in the documentation of the comsol heat conduction in a slab tutorial see next page. A more detailed description of the phenomenon and the modeling process can be seen in the blog post designing new structures with shape optimization. A finite element formulation for thermoelastic damping and roukes 1. These models show how to model thermoelastic damping in a mems resonator using fully coupled thermal and structural mechanics equations. Coventorware tutorial presented by brian pepin 11072011. Multiphysics modelling and experimental validation of. Accuracy of fully coupled loudspeaker simulation using comsol. The device is poled along the radial direction of the sphere, requiring the definition of a new local system of coordinates.
This tutorial shows how to model the acoustic waves generated in air by a hollow spherical piezoelectric material. Marinetti 2 1electrical and computing engineering department, universite laval, quebec quebec canada, g1v 0a6, saboktakin. I used the model pdf files available online to make a 3d model. To be able to compare with measurements and analytical expressions. A finite element formulation for thermoelastic damping. The physics interfaces of the mems module are uniquely suitable for simulating quartz oscillators as well as a range of other piezoelectric devices. Multiphysics analysis of thermoelastic damping effects on. Open chapter and click on comsol tab present in the bottom of the page step 2. All documentation is available in html and pdf format from the comsol help desk.
Thermoelastic damping in a coupled heat transfer and structural analysis. The displacement and temperature fields are expressed by a summation of the symmetric and antisymmetric thermoelastic modes. Comsol simulation application for thermoplastics viscosity. Analysis of thermoelastic damping effects on flexural mode simple. Study the effect of thermal stress on resonant frequency. Multiphysics analysis of thermoelastic damping effects on rf.
Comsol multiphysics, then select thermal structural interaction of. Use the heat transfer module, an addon to the comsol multiphysics simulation platform, for modeling conduction, convection, and radiation in numerous fields and applications. Air damping simulation of mems torsional paddle comsol. Comsol is the perfect tool for simulating mems and piezoelectric devices and applications. The governing equations are taken in a unified system from which the field equations for coupled thermoelasticity as well as for generalized thermoelasticity can be easily obtained. Coventorware tutorial university of california, berkeley. Heat generation in a vibrating structure comsol multiphysics. One of the tutorials shipped with the mems module shows the mechanical response of a thickness shear quartz oscillator together with a series capacitance and its effect on the frequency response. The effect of thermoelastic damping on the total qfactor of.
Thermoelastic damping is an important factor when designing mems resonators. Thermoelectric simulation using comsol multiphysics and analysis of contact resistances effects miguel a. This issue of multiphysics simulation, sponsored by comsol, inc. Analytical solution of squeeze film and thermoelastic damping. Although the mechanism of thermoelastic damping was explained long time ago by zener 3, the modern application of the theory to micro and nanoscale resonators should be attributed to lifshitz and roukes 4 who successfully predicted the thermoelastic damping dissipation in simple beam resonators. These losses result in thermoelastic damping, which is covered by this new user interface. The heat transfer module users guide comsol documentation. Ted effects on resonators are done by using comsol multiphysics software. Comsol multiphysics tutorial 2008 4 duwel a, candler rn, kenny tw et al. Employing a commercial software package such as comsol. Simulation software is becoming more and more prevalent in product development and design.
The physical parameters of single crystal silicon beam used for simulation are shown in table 1. Thermoelastic damping, thermal stability piezoelectric effects ex. I am successfully able to calculate the the eigenfrequency but havent been able to incorporate the damping term due to thermal stress. A finite element formulation for thermoelastic damping analysis. Our new method is introduced in this research study that involves use of experimental. The comsol sales and support teams are available for answering any questions you may have regarding this. Multiphysics modelling and experimental validation of microelectromechanical resonator dynamics citation for published version apa. Yee, and rimantas barauskas estimation of thermoelastic damping of vibrations in microelectromechanical systems resonators. An introduction to shape optimization tutorial model comsol. Comsol mems tutorial pdf the application gallery features comsol multiphysics tutorial and demo app files pertinent to the electrical, structural, acoustics, fluid, heat, and. Thermoelastic damping has been identified as an important loss mechanism in mems resonators l4. The cyclic deformation of the resonator creates local temperature variations and thermal expansion of the material, which appears as damping. Keywords thermoelastic damping, eigen frequency analysis, simple fixedfixed beam resonators, thin film resonators.
The objective of this workshop is to understand the effect of damping on a mechanical structure, and how to apply damping. Finite element analysis of the generalized thermoelastic. Abstract a finite element method is used to study the thermoelastic interactions in an elastic half space subjected to a ramptype heating. These can include inductors, capacitors, coils, motors, and insulating material, where the parameters that must be measured and optimized to describe their property include inductance, capacitance, impedance, force, torque, and resistance. Finite element modelling and simulation of thermoelastical.
Pdf effect of thermoelastic damping in nonlinear beam. Prestressed micromirror one method of creating springlike comsop or inducing. A finite element analysis of thermoelastic damping in. An analytical model accounting for two dimensional thermal conduction.
Simulation of heat generating in a vibrating structure using. Comsol lep tutorial for tank flow system two cstr in series step 1. Predictive modeling of thermoelastic energy dissipation in. Thermoelectric simulation using comsol multiphysics and. Prestressed micromirror one method of creating springlike comsop or inducing curvature in thin structures is to plate them to substrates that are under the influence of residual stresses. Engineering mems resonators with low thermoelastic damping article in journal of microelectromechanical systems 156. Mar, 2020 the application gallery features comsol multiphysics tutorial and demo app files pertinent to the electrical, structural, acoustics, fluid, heat, and chemical.
Thermoelastic damping in contourmode inplane vibrations of rings, disks, and elliptical plates is investigated on. I was trying a model from the comsol gallery which used damped eigenfrequency analysis for their model solution. The video tutorial featured in this blog post shows you how to set up and run a simulation using comsol multiphysics. The extension affects obviously the quality factor of thermoelastic damping. Accuracy of fully coupled loudspeaker simulation using. This is desirable in both mass sensing and timing applications. If you are reading the documentation as a pdf file on your computer. This paper considers ring resonator based rate sensors and investigates the influence of design changes to the ring and support legs on thermoelastic damping, which is the dominant dissipation mechanism. Thermoelastic damping ted is a critical loss mechanism in numerous high q. The fluidstructure interaction interface of comsol multiphysics software is used to study the 2d interaction of torsional paddle resonator with air and evaluate the damping torque and quality factor. By selecting the new thermoelastic damping check box, the problem will become twoway coupled when a timedependent problem. Structural mechanics, or solid mechanics, is a field of applied mechanics in which you compute deformations, stresses, and strains in solid materials.
Direct detection of akhiezer damping in a silicon mems. Jul 12, 2019 comsol mems tutorial pdf the application gallery features comsol multiphysics tutorial and demo app files pertinent to the electrical, structural, acoustics, fluid, heat, and. Viscous damping, which relates the stress to the strain rate, can be used both in the time and frequency domains. In this paper, the quality factor of the resonator is computed by. The effect of thermoelastic damping on the total qfactor of stateof. Analysis of ultrasonic elastic waves in vibrothermography. Hi, i have been trying to do thermoelastic damping simul ations in comsol 4. This tutorial shows including thermoelastic damping effects in a mems resonator with the new thermoelasticity user interface in the mems module. Because the direction of poling imparts anisotropy to the material response, it is critical.
This tutorial shows including thermoelastic damping effects in a mems. Often, the purpose is to determine the strength of a structure, such as a bridge, in order to prevent damage or accidents. Abstractanalysis for the generalized thermoelastic lamb waves, which propagates in anisotropic thin plates in generalized thermoelasticity, is presented employing normal mode expansion method. In the solid mechanics and membrane interfaces, it is now possible to specify viscous damping together with the linear elastic material. How to model structural mechanics in comsol multiphysics. Electrical devices come in many shapes and sizes and often have to connect and correlate with many other devices in an electrical system.
Test out how it can work for you by attending a free handson workshop where a complimentary trial of comsol multiphysics and its modules will be made available for you. Baiju modeling and simulation of thermoelastic damping ted is an important issue in the development of actuators, mems. The effect of including thermoelastic damping is that a heat source term, proportional to the rate of stress change, is added to the heat. In the comsol multiphysics software any number of physics can be combined in one and the same simulation. For applications requiring high performance angular rate measurements it is important to be able to design mems rate sensors with high quality factors q. By comparing these q measurements on resonators with variations in design, dimensions, and anchors, we have been able to show that gas damping, thermoelastic dissipation, and anchor damping are.
In the thermal expansion multiphysics coupling, you can now select whether or not the time derivative of the stresses should act as a heat source in the heat transfer problem. Thermoelastic damping in a mems resonator comsol multiphysics. You are also more than welcome to send off a quick question to us and find out more. Effect of thermoelastic damping in nonlinear beam model of mems resonators by differential quadrature method july 2015 journal of applied mathematics and. This example shows how to model thermoelastic damping with comsol. Evaluation of thermoelastic damping in micromechanical resonators with axial pretension. Multiphysics interface for thermoelastic damping in mems u u u userdefi ned materials written in c u u u adhesion and decohesion for mechanical contact u u u multiphysics interface for magnetostriction u u u new plasticity material models u u u stress linearization evaluation of membrane, bending, and peak stress u u. Furthermore, this example may also be defined and modeled using components from the following product combinations.
Finite element analysis of thermoelastic damping in contourmode. Aug 24, 2012 in this video tutorial you will learn how comsol multiphysics can be used to model the microwave heating of a waveguide. Introduction to structural mechanics comsol multiphysics. Engineering mems resonators with low thermoelastic damping. Squeezefilm gas damping of a vibrating disc this benchmark model. Publishers pdf, also known as version of record includes final page, issue and volume numbers. Jun 25, 2019 thermoelastic damping is an important factor when designing mems resonators. Thermoelastic waves in anisotropic plates using normal. This stepbystep instructional video will guide you through the modeling workflow, with an emphasis on structural mechanics modeling. A second mechanism contributing to the slow temperature rise in a vibrating structure is called thermoelastic damping, and represents the energy conversion between mechanical and thermal energy. This manual gives you an introduction to modeling in femlab by taking you through the basic steps of the modeling process, from generating the geometry to postprocessing. Contents 7 theory for moisture transport 209 theory for moisture transport in building materials.
Feb 01, 2017 lorant olasz shows how to enable automatic scaling for viewing your comsol multiphysics simulation geometry, mesh, and results. Femlab heat transfer tutorial rev rowan university. School of mechanical engineering, university of birmingham, edgbaston, b15 2tt. Finite element analysis of thermoelastic damping in. The effect of resonance frequency by changing the torsional spring on air damping is investigated. Introducing heat transfer modeling software from comsol. Thermoelastic damping can be directly incorporated into a model through a setting in the thermal expansion multiphysics coupling. Multiphysics interface for thermoelastic damping in mems. Designing and modeling electrical systems and devices.
This example exemplifies the basics in how to optimize shapes using comsol multiphysics. For example, to model joule heating in a structure with temperaturedependent. Excerpt from the proceedings of the comsol conference 2010 boston. Pdf effect of thermoelastic damping in nonlinear beam model. Mechanical introduction to structural mechanics what is structural mechanics. The thermoelasticity physics interface is used to model linear thermoelastic materials.
The predicted results reveal that the quality factor of squeezed film damping is significantly affected by ambient pressure. This could be the reason why my solution is not showing desired values no damping part in eigenfrequency values, although using thermoelastic effect. The equivalent elastic and damping coefficients are determined from pressure distribution using a greens function method. Learn how to use comsol multiphysics and the structural mechanics module by conducting a static analysis of a mechanical structure.
Temperature dependence of quality factor in mems resonators. Comsol multiphysics true multiphysics everything can link to everything flexible you can model just about anything. Squeezefilm gas damping of a vibrating disc this benchmark model computes the total force acting on a vibrating disc in the frequency and time domains and. The effect of a dielectric block is included in the model. Modeling mems and piezoelectric devices comsol multiphysics. Damped eigenfrequency analysis comsol multiphysics.
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