Transient Laminar Fluid flow and heat transfer in Porous media
Hi I'm trying to model coupled physics of transient steam flow through a porous medium and heat transfer between steam and the porous medium material and wall. The porous medium has a low thermal...
View ArticleCharge conservation
Hi, I am new to COMSOL and I don't think I really understand where to use "Charge conservation" in the ES and in Plasma modules. Going through tutorials show that people use it if you have a dielectric...
View ArticleCall functions in 4.3a
Hi I created an interpolation fonction in the global definitions node. I need to use that function as an excitation in a bondary condition and simulate according to that interpolation. So, I put "Int1"...
View ArticleSave data to a text file using MATLAB LIVELINK with COMSOL
Hi All, I have one COMSOL GUI model which runs perfectly. I save the model as .m file and run in MATLAB. In the COMSOL desktop, I use the export command to extract data. Therefore, I am expecting when...
View Articlebeam vibration by a shaker
Hello, eneryone. I am doing a project simulating a simple beam structure vibrated by a shaker. The left end of the beam is fixed with the shaker. If I want to set the beam vibration acceleration at 10...
View Articlehelix with rectangular cross section.
hello I need to know how to make a helical ribbon with rectangular cross-section. thanks
View ArticleDeformation of liquid droplet
I am new to COMSOL, so I am referencing a work on deformation of liquid droplet impacting a solid surface. I tried to recreate the same model as that work. But I ran into several problems. As I tracked...
View Articlespiral coil
Hi I am trying to model a spiral coil in 3D. the coil wire is of rectangular cross section and tightly wound so that there is a very thin gap between windings and it is filled with epoxy. It is not...
View ArticleUnits not considered
Hi I define a constant NA with units cm^-3 and a function f(x) = NA*exp(-(x/k)^2), where 'x' and 'k' are in meters making the units of f(x) essentially cm^-3. However, in the variables list, where I...
View ArticleDiode example solved but strange
Hi I tried to solve the semiconductor diode example from the model library but simplifying it a bit. In particular, I discarded the rounded corner and just made it a text book like pn-junction. It...
View ArticlePCF, PML
Hi, I am designing a PCF with hexagonal pattern having five air hole rings. pitch = 1 um. air filling fraction = 0.90 i have used circular PML to get the imaginary part of refractive index. what should...
View ArticleHC-PCF
Hi , I would like to calculate the hollow PCF, as I know, normally we should know the bandgap of the fiber, then calculate the fundamental mode. is it feasible to calculate the bandgap by using Comsol...
View ArticlePreview of open model
When opening model files, there is possibility to show the preview of model. But all models result in the message "No preview available". How may I switch this possibility on?
View ArticleQuestions for electric fields in 2D vs. 3D model of capacitor.
Hi guys. I am trying to model a structure, which has a capacitor build into it with SiO2 and air as dielectric. For this I started to model a 2D structure and plotted the electric field as "electric...
View ArticleJoule Heating with Thermal Expansion Simple Setup
Good Afternoon Everyone, I am new to COMSOL but have used other software for simulations (ANSYS), I am currently trying to model an aluminum wire embedded in a polyethylene substrate, just doing a 2D...
View ArticleCantilever MEMS, Eigenfrequency vs Temperature
Hello everybody, I'm trying to simulate the change of the eigenfrequency when the cantilever temperature increases. In theory, when the temperature increases the eigenfrequency decreases. I built a...
View ArticleMagnetorheological Elastomer Issues: Rotation Matrix and Hyperelasticity
Greetings, I am working on a project that uses magnetically active elastomers(MAE) being subjected to external magnetic fields (H). The internal magnetization of the elastomer (M) is oriented in the...
View ArticleHeat transfert / PDE equation
I would like to draw the temperature profile within a sphere cooled outside, whose equation is as follows: diff(T,t) = (k/rho*cp)*diff(diff(T,r)) + (k/rho*cp)*(2/r)*diff(T,r) initial values: t=0 and...
View ArticlePorous media modeling with wall effect
Hi I'm trying to model coupled physics of transient steam flow through a porous medium and heat transfer between steam and the porous medium material and wall. The porous medium has a low thermal...
View ArticleFluid-Structure Interaction
Hi, There is a sample Fluid-Structure interaction problem given in Comsol model library. In this module, is it possible to specify the deflection of cantilever in terms of relation between y and x, y...
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