Encountering error during meshing
when I try to run a mesh i encounter the following error message: "Edge is much shorter than the specified minimum element size." I do not know what this means and any advice on how to get rid of this...
View ArticleExport water table time series data from periodic Richards equation solution
Hi, is there an (easy) way to export a time series of the water table elevation (p=0 contour) from a time-dependent (periodic) Richards equation model? I have a 2D vertical rectangular grid with a...
View Articleresidual computation error
when given for solving, an error occurs as shown below: error: time: 0.005389521413017638 Error in residual computation extrusion_coupling_operator_interpolation_failed...
View ArticleCoupling transport of diluted species and laminar flow modules.
I am trying to couple the transport of diluted species and the laminar flow modules. What am I doing wrong? I'm guessing it has something to do with my solver settings. Do I need to solve the laminar...
View ArticleNegative power of zero - error
Hi, I am attempting to model the continuous casting process of steel. The molten steel is poured in from the top of the geometry, it then enters the water cooled copper mould, and then it is...
View ArticleDivergence of a vector field
Hello, I am new to COMSOL and I am trying to build a physics interface module. I would like to calculate the divergence of current density. I defined a variable for the same, but when I input the...
View ArticleVoltage sweep; plot IV curve for current through wire
Hi there, I have just started using COMSOL and am trying to make a specific model but running into trouble. The first part of the model is as follows: - Model a wire of specific material and sweep...
View Articletime-dependent problem, singularity error
Hi, I am trying to solve a time dependent, multiphysics problem using "Transport of Diluted Species" and "Electric Current". In my model there are basically two electrodes inside water, and pulses are...
View Articletime information of streamline
Hi I solved a laminar flow diffusion mixing stationary problem for a simple system. In the result I plot 1000 streamlines. I need to know the mixing time for every streamline so I have to get the time...
View ArticleInduced voltage in a coil
Hi, I'm modelling an eddy current testing probe with the AC/DC module. The model is 3D, and I have a transmitter coil with an applied current and also a receiver coil with no current. I'm doing a...
View ArticleInduction Heating, equivalent resistance
Hi, when I simulate an induction heating process the value of the equivalent resistance decrease over time. Shouldn't it increase because of the increase of the resistivity due to the increase of the...
View ArticleInteraction of Rayleigh wave with solid where a substance is placed upon a...
I want to make a simulation of a device where Rayleigh wave will be generated and that wave will drive a substance loaded upon the wave generating substrate. Already I have tried with different physics...
View ArticleHow to definition value between 2 boundary and use it in domain between them?
I want to define difference of P(x,y) between to boundary (such as boundary 1&2) and use it in the domain between that's boundary. suppose that boundary 1 location is (x,1[mm]) & boundary 2...
View ArticleComsol 3.5 and Matlab - boundary ID
Hey, I have big problem with Comsol Script. At work we just have the very old Version 3.5 - the new one we will maybe get during this year but I cannot wait until this future-date! I have a geometrie...
View ArticleComsol does not use all RAM available
Dear all, running Comsol on my laptop, I see that it uses only 4-5 Gb of the available 16Gb RAM, and in fact it takes a very long time for simulation of time-dependent 3D problems. I don't have any...
View ArticleJacobian
Hello!! Someone knows how to compute the matrix jacobian, the determinant and the inverse of that with the COMSOL? Thank you, Suelen
View ArticleDefining boundary conditions from previous solution
In the frequency domain RF module, I first computed solution 1. Next, I would like to define the electric field on the boundary for solution 2 (same mesh as solution 1) as the cross product between the...
View ArticleConfinement loss calculation of PCF using PML
Hello, I want to calculate the confinement loss of a Photonic Crystal Fiber using a perfectly matched layer, however it is still not clear how to implement this PML, my questions are what material this...
View Articlepost processing
hi i am working on 3D blood vessel with non solid wall. i have finished the study part and now i have problem with plotting velocity , pressure and shear stress vs length. i wanted to attach the mph...
View ArticleMatrix exponential
Dear folks, I have a system of ODE of the form y_dot = A(y) * y, where y_dot is time derivative of vector y and A(y) a tensor (n by n Matrix form). For numerical approximation, I need to calculate...
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