How do i make a nonlinear solver converge in comsol multiphysics. This example treats the modeling of electroosmotic flow in porous media. Extensive information about command line modeling using comsol script is available in yet another book, the comsol multiphysics scripting guide. Comsol webinar modeling coils and electric devices youtube. The model equations are solved using the finite element software comsol. To account for the steric comsol multiphysics software application effects of the. The ac electroosmosis is mostly based on the coulombic interaction between an. This stepbystep instructional video shows you how the electromechanics interface in comsol multiphysics couples and solves mechanical and electrical problems. Find out all of the information about the comsol product.
Simply log in and follow the onscreen product download directions. Simulating electrokinetic phenomena in microfluidics. Comsol uses finite element in order to solving problems. Geometry and dimensions of the microchannel l1 l5 h 10. By definition, electroosmosis refers to the motion of a liquid induced by an applied potential across a microchannel. Learn how to model microfluidic devices in comsol, such as.
The purpose of this study is presenting an active micromixer, which is based on ac electroosmotic flow driven on 3d micro wires. By definition, electroosmosis refers to the motion of a liquid induced by. Murdoch for teaching me cfd simulation with comsol multiphysics, mr. Electroosmotic flow or electroosmotic flow, often abbreviated eof. Dalton1 1university of calgary, calgary, ab, canada abstract electrokinetics has many applications in a wide range of areas, such as labonachip and. Author links open overlay panel kuanrong huang a zhou. Watch this archived webinar to learn how to model electroosmotic flow, a useful skill for optimizing devices like micropumps and micromixers, with the comsol multiphysics software and addon microfluidics module.
Microfluidic mixing on application of traveling wave electroosmosis. In electroosmosis, the uncompensated ions in the charged electric double layer edl present on the fluid surfaces are moved by an electric field, causing a net fluid flow. The equations that are solved are the continuity equations for flow velocity and current density together with a mass balance using the electrokinetic flow. Mathematical modeling of ac electroosmosis in microfluidic and. Multiphysical modeling of dc and ac electroosmosis in.
In order to carry out the numerical simulations, a strongly anisotropic mesh of finite elements is developed. Electroosmotic flow in porous media comsol multiphysics. Electroosmosis article about electroosmosis by the free. We report the presence of trapping points near the vertex of the triangular electrode in our simulation. Microfluidic mixing on application of traveling wave. In addition to using multiphysics modeling for your own projects, you can also turn your models into simulation applications and digital twins for use by other design teams. Please login with a confirmed email address before reporting spam. Currently available theoretical models for eo flows were embedded in the software and solved numerically to evaluate the effects of channel geometry, frequency of. Model of electrokineticflow driven by an ac electric field in a microchannel. Pdf numerical simulation of the electrical double layer based on. Enhancement of heterogeneous immunoassays using ac. The numerical simulations are performed using the finite analysis software comsol multiphysics version 3. Strongly nonequidistant and anisotropic meshes of finite elements had to be used due to formation of thin edls. Poisson equation based modeling of dc and ac electroosmosis.
The first model demonstrated that the presence of electroosmosis might intensify the flux of messenger proteins to the nucleus and allow the efficient transport of the negatively charged phosphorylated messenger proteins against the electrostatic repulsion of the. Modeling electroosmotic flow and the electrical double layer. Bidirectional flow induced by an ac electroosmotic micropump with dc voltage bias. In order to solve governing equations of ac electroosmosis, a commercial software comsol multiphysics is implemented. Did you know that designing electrical systems and devices is faster and cheaper with simulation. How to model electromechanics in comsol multiphysics. Because electroosmotic velocities are independent of conduit size, as long as the electrical double layer is much smaller. After watching this video, you will have a solid foundation for creating models of. Numerical simulation of the electrical double layer based. Nonplanar asymmetric electrodes, on which an ac electric field is imposed, are deposited on one channel wall.
In addition, we discuss topics such as how to treat the electrical double layer and turning a model into a userfriendly simulation app. The book in your hands, the acdc module model library, provides details. Electroosmotic flow is the bulk liquid motion that results when an externally applied electric field interacts with the net surplus of charged ions in the diffuse part of an electrical double layer. The term electroosmotic flow and electroosmosis are generally used interchangeably in the context of micro and nanofluidics.
Contact a supplier or the parent company directly to get a quote or to find out a price or your closest point of sale. Bidirectional flow induced by an ac electroosmotic. Can anyone help with the following error in comsol. The products, devices, and components you design for the static or lowfrequency range need to operate safely in the real world. Everything in my simulation looks ok but the flow profile looks weird. A set of auxiliary variables to characterize the ac micropump was defined, see the supplementary material. Modeling of an acelectroosmosis based microfluidic mixer. Ac electroosmosis, ac electrothermal, induced charge electroosmosis, traveling wave dielectrophoresis, and liquid dielectrophoresis. Lowvoltage electroosmotic micropump solved with comsol. Ac electro osmosis aceo is a nonlinear electrokinetic phenomenon of inducedcharge electroosmotic flow around electrodes applying an alternating voltage. The cell combines pressure and electroosmotic driven flow. It is a common practice to optimize the design of inkjet printers, labonachip devices, and cell sorters with microfluidics simulation software. View the specification chart to find your ideal combination.
Driving the flow with an electric field allows for the fabrication of. In the field of microfluidics, the flow is often driven by an electric field. The ac electroosmosis is mostly based on the coulombic interaction between an imposed ac electric field and a mobile electric charge temporally arising at electrolyte metal electrode interfaces. Numerical modeling and analysis of electro osmotic.
Numerical simulation of the electrical double layer based on the. Overview classical electrokinetic phenomena, such as electroosmotic flow and electrophoresis, are linear in the applied voltage and thus cannot produce any net flow under alternating current. Ac electrothermal flow pumping acet body force posted 16. Therefore, the development of a lowvoltage cascade eof pump is. Poissonboltzmann models for ac electroosmosis flows. The combination of comsol products required to model your application depends on several factors and may include boundary conditions, material properties, physics interfaces, and part libraries.
Simulations of interdigitated planar electrodes indicate that optimum electrode geometry electrode width and spacing scales with the chamber height and that binding times can. Comsol multiphysics is a crossplatform finite element analysis, solver and multiphysics simulation software. To generate acffet, a gate electrode ge is placed inside an. Fast biofluid transport of high conductive liquids using ac electrothermal phenomenon, a study on substrate characteristics a. Acdc module modeling software electromagnetic field. Mathematical modeling of ac electroosmosis in microfluidic. These problems have led to an intense search for more efficient mixers for microfluidic systems. Timothy pruett for helping me making sinusoidal spacers with 3d printing, the students in the creative inquiry program for setting up the bench scale ro system. In our research group, we usually employ comsol multiphysics software for both the stationary and the nonstationary simulations. Modeling electroosmotic flow and the electrical double. In smallscale microfluidics processes, electroosmosis, electrothermal effects, and electrokinetic instabilities are responsible for fluid motion and electrophoresis and dielectrophoresis dep cause particle movement, such as in cells. Mathematical modeling of ac electroosmosis in microfluidic and nanofluidic chips using equilibrium and nonequilibrium approaches article in journal of applied electrochemistry 405. The numerical results were generated through simulations performed using comsol 3.
Customize comsol multiphysics to meet your simulation needs with applicationspecific modules. Introduction 5 introduction the ac dc module is used by engineers and scientists to understand, predict, and design electric and magnetic fields in statics and lowfrequency applications. The analytes in the system are positively charged sodium and a negative ion with the same. This study mainly focuses on ac electroosmosis aceo, which originates from the electric double layer. Particular functionality may be common to several products. Comsol multiphysics electric currents physics and laminar flow physics are used to simulate dielectrophoresis and ac electroosmosis. Simulating electroosmotic flow with the microfluidics module.
In this article, enhancement of heterogeneous immunoassays using ac electroosmosis was studied through the use of finite element modeling and fluorescent immunoassays. Simulation of reverse osmosis and osmotically driven. I checked everything with the old comsol library model electrokinetic flow in biochip3. The analytes in the system are positively charged sodium and a. Its spatial characteristics are 100 microns wide by fifty microns long. Numerical study on ac electroosmosis in microfluidic channels. Does anyone know why the ellectroosmotic flow is not a flat profile in comsol or i messed it up. Keywords tas, biomems, electroosmosis, comsol multiphysics. It allows conventional physicsbased user interfaces and coupled systems of partial differential equations pdes. In ce, the capillary columns consist of silica with silanol groups exposed on the inner surface. Electroosmosis also electroendosmosis, the movement of a liquid through capillaries or porous diaphragms upon application of an external. Electroosmotic flow eof describes the movement of ions through a solute under the control of an applied potential. The microfluidics module provides a specialized electroosmotic velocity boundary condition as one of several fluid wall boundary conditions.
You can try fluent software which uses the finite volume that is so. This model takes advantage of electroosmosis to mix fluids. The comsol multiphysics software requires discretization of spatial. The system consists of a compartment of sintered porous material and two electrodes that generate an electric field. Driving the flow with an electric field allows for the fabrication of pumps and mixers without moving parts. Ac electroosmosis and dielectrophoresis for trapping. Comsol provides an ide and unified workflow for electrical, mechanical, fluid, acoustics and chemical applications.
Multiphysical modeling of dc and ac electroosmosis. An experimental study of 3d electrodefacilitated particle traffic. Fieldeffect control on nonlinear electroosmosis in the transverse direction greatly. The numerical analysis was carried out in comsol multiphysics software. Computer simulations were performed within the comsol 4. The exposed silanol groups are ionized above ph 3, therefore creating a negatively charged inner capillary surface. The implementation procedure of this multiphysical problem in a cfd software and.