Expression error
After running a simulation for a 3D structure with a magnetic field going in the z (vertical) direction, COMSOL returns the following error: Division by zero. - Function: / Failed to evaluate...
View ArticleHow reflection is modeled in acoustic module?
Hi,Recently I am modeling a transmission and reflection problem using background pressure field+PMLs. I found that the scattered field (acpr.p_s) can only be visualized in background field. The value...
View ArticleDefining a barycenter velocity in the model
Hi all I am using fluid-structure-interaction(fsi) interface to simulate a microfludic device,which allows cells flowing through the channel.As the length of the channel is not very important for my...
View ArticleVolume Average Data Set
Under the derived values tab, the option Volume Average determines the average value for an appropriate expression over a specified component of the resolved mesh geometry. I'm wondering if there's a...
View ArticleAttempt to evaluate negative power of zero.
Hi all,I'm trying to do corona discharge with the electrostatic and transport of dilute species modules, and currently got stuck with this probelm: Attempt to evaluate negative power of zero. -...
View ArticleRun comsol from matlab
My comsol version is 5.3 and Matlab is 2018a. I tried to run comsol using livelink for Matlab. I first loaded my comsol file and Matlab gives me following info:ans = COMSOL Model Object Name: RRAM.mph...
View ArticleSegregated Steps Order
Hi everyone,I have a mass transfer equation with two reaction source terms which is coupled with fluid flow and energy equation. I've tried fully coupled solver, but it didn't work. I'm going to run...
View ArticleLaplace stationary equation & Neuman Conditions
Hi Sorry to disturb you but I can’t manage to solve a very simple problem and it drives me crazy. For a college project I have to code some finite element method about current density distribution on...
View ArticleComsol crashes
If I choose "COMSOL Multiphysics.app" to open mph the files it always crashes. Is there anything I can do.
View ArticleBreakdown study thin film oxide
Hi all,I am intersted to study electric field profile in the thin film oxide before breakdown. I have a device with oxide film sandwiched between metal and semiconductor (schematic attached). I do not...
View ArticleElectric Field Value corresponding to AC voltage of different frequency
I have a 2D model of parallel plate capacitor with a dielectric in between the plates. I have to apply an sinusoidal voltage of 2000 V, 10 Hz at one plate and ground potential at other plate. I need a...
View ArticleHow to simlulate cartridge heaters in an instrument
Hi,I'm try to solve a solid heat transfer problem with cartridge heaters in an instrument. To simulate the cartridge heaters I choose the boundary of cylinders as a heat source. The heating power of...
View Article4-point probe measurement in COMSOL
For an experiment I am measurering the impedance of a piece of conductive rubber with a 4-point measurement (see the schematic image and picture of the set-up). I am trying to simulate this in COMSOL...
View ArticleClamped plate with an absorber
Hello,I am trying to model a clamped plate with a spring-mass system attached as shown in the figure (attached). I am using the structural module for the plate and Lumped Mechanical system for the...
View ArticleHow to plot/ calculate axial strain of a surface?
Dear all,I am bulge testing a diaphragm and want to calculate the axial strain along the length of the bulge. I tried plotting some expressions related to strain but didn't get the soulution I was...
View ArticleHow to measure the homogeneity of an electric field in Comsol?
I need some value that measure the homogeneity of an electric field lines.Any idea?
View ArticleHow can I couple Convection-Diffusion Equation with Solid-Mechanics in COMSOL?
Hello!Could someone help me?In my problem I need to use the stress calculated at Solid-Mechanics module to use in the initial conditions at the Convection-Diffusion problem. Someone knows how to do...
View ArticleComputing the sensitivity using the Sensitivities at the Physics node and...
Hello,Please, find my attached mph file. rho0 is a variable. I needed the sensitivity of my objective integral (ps.Ws) with respect to a control variable (rho). I have defined the objective integral,...
View ArticleConvert a plane surface to solid in 3D
Hi All,I want impose some boundry conditions on a plane surface in 3D. But when I tried to use convert to solid options, it gave the following message. "Output object is empty. It is not possible to...
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