about 'Warning : Re-ordering of null vectors failed"
Dear all, I'm trying to simulate the dynamic behaviors of the linear control solenoid valve. The spool motion is determined by the force balances, which are calculated from each field, and a...
View ArticlePhotonic crystal fiber
I am trying to model a photonic crystal fiber with liquid crystal filled holes.. I am a starter and it would be really helpful if any one can help me regarding the resources from where i can learn the...
View ArticleHow to calculate photonic band gap, transmission and reflection spectra?
We want to get photonic band gap, transmission and reflection spectra of 1D or 2D PC. Could you help me how can I obtain band gap and Transmission/Reflection spectra of 1D or 2D photonic crystal? Or...
View Articleabout heater simulation in the room
Hello! I am use comsol 4.3a , and use the non-isothermal flow physics to simulate the heater in the room. And the room has a door , and I want to set the door is open, and it is connect to the...
View Articlerf mems switch design (comsol 4.2a)
HeLLO, i'm working on designing a switch that should work on rf range. I'm able to draw 2d structure in work plane but still not able to fix one side of the cantilver beam. i hve following questions,...
View ArticleEigen frequency analysis
hi, i am dealing with a nanotube sensor...can i use eigen frequency study step to find frequency at which displacement is maximum or should i use some other study step..
View ArticleUsing a Gaussian Pulse
Hi everyone, I'm actuallay working on a modeling of a laser pulse which is heating a front of a material in order to determinate the diffusivity, my current issue is that i would like to model my heat...
View Article[SOLVED] Comsol v4.3.0.233 crashes
Hi, Today, after restarting my machine I opened several applications and I was logged out from my desktop session. After checking one by one, I get to see it was comsol that was giving problems. I've...
View ArticleChanging the relative repair tolerance seems not to be effective in any way
I need to define a geometry that is very awkward but it's necessary, It's a sphere with a very big radius compared with the thickness of a single layer (1000 times smaller, e.g. s/r = 1e-3, where s =...
View ArticleConvergence of time dependent and linear solver
Hello All, I am trying a model in which electrodes can electrically stimulate certain layers having different conductivity (input being a biphasic pulse train). Using time dependent study, the model is...
View Articletime interval for automatic remeshing
Hi, I would like to know the COMSOL keyword for the time interval when using the automatic remeshing module. I want to define a criterion based on the time that's why I need to know the actual number...
View ArticleIntegral Constraint
Hi, I am using the Nernst Planck Module (chnp) on Comsol 4.3 and I want to create a constraint so the total current in a boundary it's equal to 0, but I have no idea how to do it. Can any body help me?...
View ArticleInitial values error using mapped mesh
Hello, Every time I try to use a mapped mesh for a time dependent simulation I have the following error : --- The following feature has encountered a problem : failed to find consistent initial values....
View Articlegas mixture
Hi I am trying to model an ejector with 2 inlets and one outlet. In the first inlet I have hydrogen with low pressure, in the second inlet I have (hydrogen 30% + steam 70%) with a higher pressure. The...
View ArticleOverride not-applicable boundary
Hi, This may be easy but I don't see how to do it in V4.3a. In V3.5a it was not hard. I would like to apply convective cooling at an interior boundary in my model. Currently, all the interior...
View ArticleExport Image through script
I would like to be able to save an image of my plot using a script. I thought opening my script and going to export image in the GUI would add the steps to my m file but that didn't work... Thanks
View Articlemicrofluidics
hai all my geometry is a rectangular having 10mm in x direction and 1mm in y-direction. the first half ( up to x=5mm) consists of one fluid and second half consists of other fluid having same...
View ArticleState Space Export
Hi , i have build a simple cantilever beam model using time depented model. after defining the points of forces and parameters, i want to export the model to matlb (State Space Matrices) so i could...
View ArticleHow to plot the relative error?
I've just spent more than a whole day troubleshooting my model. However, if I could plot the relative error over the geometry, I believe it would have been solved in minutes. There was a problem...
View Articleacceleration due to gravity Laminar flow
I want to give acceleration due to gravity effects to fluid in Laminar pipe flow, any one know how to give,????? I have tried by applying domain volume force like 9.81*density of fluid but i am not...
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