How does Comsol compute solutions?
Hi, I have a model of a thin wire inside a big cylinder and I put an electric potential of -10kV on it. I have plotted a graph of E field normalised against x coordinates (which is in the direction...
View ArticleUsing Current derived from Voltage
Hello All, I have a situation where there is essentially a 2D box in a water tank cross section. I know the boundary voltage of the box. What I'm hoping to do is to add objects into the water to...
View ArticleThe relative error is greater than the relative tolerance..Error!!!
Iam a newbie to comsol. And Iam learning comsol for my research. I simulated my first simulation and I got the below mentioned errors. Failed to find a solution. The relative error (4.6e+004) is...
View ArticleMeaning of "Segregated solver steps do not involve all components"
Hi, I am making a simple model of a microwave waveguide, something I have done before, but I cannot get the solution to compute because of this error (attached jpg). Usually when I get COMSOL errors,...
View Articlehow to set the contact pair correctly?
I have a question about my subject. So when i set it, what i need exactly? I set my boundary condition about which place get received some force. And i set the contact pair. there are 3 parts in my...
View ArticleRandom Function
Hi, It may sounds a simple question but anyway, A random function of, 3 arguments, uniform distribution, mean 0.5, range 1, using it as conductivity property (rn1(x,y,z)). once running the simulation...
View Articleconjugate heat transfer; solution not convergent
Hi everybody. I need help with my model. I’m modeling the heat transfer of a CdTe detector connected to some power electronics. The geometry dimension is more or less of 200 mm^3. I’m using both the...
View ArticleFailed to find a solution. Divergence of the linear iterations. Returned...
Module: AC/DC, Study: Frequency Domain Sir/Ma'am, I have modelled a coil which scans the surface of a sample material for any superficial cracks. For this, i have introduced a small crack and also i...
View ArticleUndefined value found in the equation residual vector.
I am trying to model a pem fuel cell. Although I have entered all parameters and values, i have some errors as follows; Undefined value found. - Detail: Undefined value found in the equation residual...
View ArticleParametric Sweep gives different results with separate calculations
Hello, Strange things happened when I use Parametric sweep function today. Initially, I solved a model by setting a parameter as a fixed number ( say "a"). Then I swept this parameters with different...
View ArticleStudy1 is sweep of the wavelength and the consequence is used in Study 2, but...
Hello all ! I'm puzzled that how to calculate the EQE of the solar cell , I used the light(rf module) to calculate the G (sweep of the wavelength) and electrostatics1 to calculate the phi0; two...
View ArticleCOMSOL simulation for heat and mass transfer across membrane for membrane...
Hi, For your information, I am developing a COMSOL simulation for the direct contact membrane distillation (DCMD) process. It is actually a process which involve the heat and mass transfer from the...
View ArticleDifferent convergence requirement (relative tolerance) for different...
I am working on a time-dependent model that couples two different physics branches. If I disable the second branch in the time-dependent solver, I can get a solution to converge with a relative...
View ArticleHow to import Temperature Data to the model
Hi, If I have temperature data as a function of location (X,Y,Z) in the spread sheet format, how could I import it to my model? I am looking through the manual and discussion forum but still fail to...
View ArticleImproved convergence when restarting simulation from recovery file
Hi All, when I restart a parametrical simulation from recovery file (after comsol crash) , the model convergence is significantly improved. What changed in comparsion to the initial simulation? Did...
View ArticleRelative error is greater than relative tolerance error
Hello all, I am new to Comsol and am trying to do a very simple simulation so familiarize myself with the software. I am using the Joule Heating and Thermal Expansion module in Comsol and my model is a...
View Articlehow to optimize the result of comsol with matlab??
Hello everyone! I want to know how to optimize my problem. already i got the result from matlab using the m.file which is from Comsol. Afterthat, I don't know how to solve that... Because I didn't use...
View ArticleTrouble Setting up Non-Isothermal Flow through a Tube
Hello all, I've been having difficulties setting up a non-isothermal flow study for a project; we've been trying to use COMSOL to back up some of our experimental results. We were able to get a fairly...
View ArticleMelting ice below rock using deforming mesh but without Lagrangian. Is there...
Hello, I have a question about the setup similar to the melting tin model. I have block with two layers, one on top of the other. The upper layer is granite, the lower layer is ice. On the upper...
View Articleself-consistent schrodinger-poisson equation
I want to solve the self-consistent schrodinger-poisson equation for modeling semiconductors devices and i need a help. Thanks Nadji.H
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