Secondary current distribution
In the steady-state research case of high-temperature proton exchange membrane fuel cells, a secondary current distribution model was adopted, where a fixed boundary potential E_cell condition was...
View ArticleDifference between current density and induced current density
Hello, I'm using the AC/DC module and I need to know the difference between "current density mf.Jx, mf.Jy,mf.Jz"(apparently it's the quantity from Faradays law of induction) and the "induced current...
View ArticleMicrostrip Patch Antenna Radiation Pattern
I examine the "Microstrip Patch Antenna" example in the application libraries. I just want to see the radiation pattern of the antenna. I selected "emw.gaindBEfar" expression to see the far-field gain...
View ArticleStatistical pit formation
I am working on a pit corrosion model and was able to describe the growth of a single pit. Is it possible to include a statistical approach into Comsol so the pits appear as a function of time e.g. as...
View ArticlePhotonic band-gap analysis queries
I am trying to further develop the Band-Gap Analysis of a Photonic Crystal [application ID: 798] model to conduct for a certain photonic crystal I'm designing. And I would appreciate any help or advice...
View ArticleUnexpected unit of input. :Function- exp
I am trying to add an equatiom ii definition node under variable section. It turns yellow showing error message as: **Unexpected unit of input - Function: exp***Why it is so? What is the mistake in...
View ArticleHow to Plot a Graph of Amplitude versus Time in Ultrasound Study
Hello Team Comsol, I was assigned to a project that acquired me to simulate or modelling the ultrasound. However, I have a problem in showing the results. I desired a graph of amplitude versus time but...
View ArticleThe direction of current density vector in Secondary Current Distribution
Hi,I'm trying to solve the Butler-Volmer equation using Secondary Current Distribution physic. The values of electrode potential and electronic potential are calculated as what is expected. But, the...
View ArticleExternal Property Package in Reactor Engineering
Hi! I was trying to implement a external package in the properties of sustances in the reaction. However, it can't run and appers unknown function (repp2hF_mixture) and the properties of the packages...
View ArticleSpectral settings in ray optics
Hello everyone, I want to ask how to input the spectral data of the known light source in geometric optics? That is, how the distribution of the wavelength of the light should be input into the light...
View ArticleHeat flux and thermal resistance
Good morning to whom it may concern,I would like to know if there is a feature on COMSOL Multiphysics 5.4 that allows the discovery of R_th and Q_dot on a model where there is only the phenomenon of...
View ArticleModeling a mixture of organic-aqueous (liquid-liquid) flow (10%-90%)
I would like to model liquid-liquid flow. one liquid is organic phase, and the other aqueous phase.I thought using volume averaging method, but I couldn't find papers on this topic. Why?I know Comsol...
View ArticleRestrict displacement for Solid in FSI simulation
Hi!Anyone kindly let me know the procedure to restrict displacement for solid in FSI simulation. My model is 3D symmetric and the problem is simialr to check valve where the valve deflects when the...
View ArticleModelling using darcy law for multiphase flow in porous media
I am trying to model a system having 2 phases. I am using physics Multiphase Transport in porous media, which by default adds two physics - Phase Transport in Porous Media and Darcy Law interface...
View ArticleDomain probe
What is the meaning of the integral order 4 (default) in the integral setting option when setting the domain probe? Does the setting of the integral order affect the result when the probe type is average?
View ArticleData From A Cut Line With MATLAB Livelink
The below post is related to an archived discussionHello,I am having a similar experience as Pierre Guilleme (linked above), but with an acoustics model. I wish to export the imaginary component of...
View ArticlePlotting / Viewing Predefined Physics Variable Reflection Coefficients
Hello world,I haven't been able to evaluate the predefined physics variable for the Fresnel reflection coefficient gop.matd1.rpf or gop.matd1.rpr in an Evaluation Group in the Results node of my model....
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