Singular matrix error
Hi, I am designing a simple 2D ridge waveguide structure on comsol but i am getting an error '' There are 1 void equations (empty rows in matrix) for the variable comp1.emw.S1x. at coordinates: (0,0),...
View ArticleMEF simulation not converging
Hello, I am simulation the electric and magnetic field using MEF of some coils at 1MHz. This is a frequency domain study but for some reason, the iterative solver never converges and approaches the...
View ArticleUsing Moving Mesh to export a geometry
Hello all, I would like to use moving mesh along with heat transfer in solids and solid mechanics in order to create an exportable geometry that I can then use in another solid mechanics study. In this...
View ArticleMore verbosity from errors
Hello im pretty new in COMSOL and Im having problems settting up a model. Working with turbulent flow + reacting flow I have the error Problem setting up multigrid Analysis x has no mesh defined for...
View ArticleProblems in assigning inlet-outlet boundary condition for a two phase flow
Dear all, I am trying to simulate a laminar two phase flow passing over a cylinder with a phase-field model where the cylinder is submerged into the water (heavier fluid), as a part of my project. I...
View ArticleUnable to understand this error
Hi all, I am new to Comsol and I am trying to give a 3D laminar flow(spf) with time dependent studies in a cluster. I am using Comsol 5.2 and I am getting the following error. Current Progress: 0 % -...
View ArticleCluster computing help
Dear all, Hello! Now I am using comsol 44 to do calculations on clusters with multi-nodes. But I meet a problem when doing so. I am using slurm to submit the jobs (.sh file is attached). Multi-nodes...
View ArticleUpdate/compute solution
Hi, I am wondering when it is appropriate to use the update solution button rather than the compute solution button. If I change only the mesh will I need to compute the solution again from scratch? If...
View ArticleFrequency domain analysis
Hi to all. I'm trying to perform an EIS with a 2d-axial revolution model. The model is composed of TCS-FP and second current distribution but when I try to activate the FP and TCS in the Frequency...
View ArticleDrawing a repeated diamond pattern?
Hi all, I am trying to make a model in which a repeated diamond pattern is cut out of an object. Basically a 3D rectangle with diamond shaped pores, the long axis of the diamonds being parallel to the...
View ArticleSolvers in COMSOL
Hello everyone! I am a newbie who seeks help in COMSOL. I have simulated a laminar flow in an annulus using direct solvers. The results match well with the problem (taken from Bird Stewart Lightfoot)....
View ArticleInitial Value Erron in Time Dependent Study
Hi Forum, I'm working on a 2D model in solid mechanics. The model was defined an initial velocity in global coordinate and a prescribed displacement in boundary coordinate system. The material is some...
View ArticleVolume Integration and Surface Integration
What is the use of volume integration and surface integration for the parameters like temperature, pressure and velocity??
View ArticleHow to make animation in control
I want to simulate the wave propagating in plate, but the animation show the stress deformation is out of the border of material, as i show in attachment. what's the reason?
View Articlevolume intergation of velocity
Hi I have defined variables SPF.Q (intop1(u)) for getting flow rate which is m^3/s but i am getting m^4/s .I don't know why because integration of velocity gives flow rate but i am not getting flow...
View ArticleForchheimer Drag 1
Hi i am doing cfd analysis for a porous media filter ,I got the answer but my flow rate is so high than the actual flow rate of the filter so then i used forchheimer drag for porous media so that i...
View ArticlePorous media modelling
Hi Whats the difference between porous media Transport properties and Transport properties in Transport of dilute species. Because I can implement in both cases the porous media, but the results are...
View ArticleFailed to find a solution
Hi all, I am using Heat transfer in Solids and Solid Mechanics modules to find the thermal stress of a PDMS micropump that contains a fluid reservoir, where the fluid will flow out due to heat. I am...
View ArticleUniaxial PMLs
Hello, how can i implement a Uniaxial Perfectly Matched Layer (UPML) in a 2-dimension problem? Also, is there any way to discretize the PML with rectangular and not triangular layers? Thanks in...
View ArticleSequential solving of several studies within one model
Dear all, rigth now I'm working on a model which requires me to split several computing steps over different studies. The model itself works without any failure but I have to start the computation for...
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