Failed to find consistent initial values. Last time step is not converged.
Hello, i'm studying a model which represents air passing in the middle of two cells of a battery.I'm facing this error: Failed to find consistent initial values. Last time step is not converged.What is...
View ArticleTurek's benchmark
Hi every one, I am using the Turek bench mark for solving fluid structure interaction problem but I have a question regarding the expression under'Global variable probe ' for lift and drag. it is...
View Articledeformable wall
Hi, I want to study the fluid flow between two walls subjected to sinusoidal waves. Basically, the walls are deforming sinusoidally (plate 1:y=b cos(k x- omega t), plate 2: y=w+b cos(k x- omega t))....
View ArticleWhy using newton-raphson for steady stokes flow
Hi, I am a beginner of using COMSOL based on FEM. I am trying to solve steady, creeping flow with stokes equation. In my understanding, the above equation is linear. However, I have found that COMSOL...
View ArticleConvergence problem with time-dependent inlet velocity
Hi, I'm simulating a coupled Laminar Flow and Transport of Diluted Species. When I put a steady inlet velocity the simulation workes perfectly. But when I change the inlet velocity to a time-dependent...
View ArticleEWOD simulation
Hi: I am currently working in a classical EWOD simulation (I have attached the model). The model uses the following modules: ES (Electrostatics): the voltage is applied through a needle. A thin Low...
View ArticleNegative pressure values at some grid points
The below post is related to an archived discussionHiI am trying to simulate fluid flow in porous media using Navier Stokes equation. It can be assumed as channel flow, but instead of hollow channel, I...
View ArticleMultiphase bubbly flow in COMSOL.
Hi, Is it possible to run bubbly flow in stationary mode? In my model, COMSOL runs in transient study but in stationary it gives a lot of errors. I have also edited the solver, but no response :( What...
View ArticleConjugate heat transfer: Unable to couple fluid and solid heat transfer...
Hi I am a post graduate student from India currently doing a project in the field of friction stir welding. I have modelled a rectangular plate as my workpiece and cylindrical fsw tool to generate heat...
View ArticleWhat is L_exiit in Laminar Outflow boundary condition in Laminar flow (spf)...
In spf physics, I like to give a flow rate as an outlet boundary condition. But I have to insert a value called 'L-exit'. What is the physical meaning of this and how do I determine this?
View ArticleConvention of pressures
Hello good morningI'm new using Comsol. I would like to know if it is possible to know the convention that software has by default for signs of pressures. I would like to know if NEGATIVE INPUT...
View ArticleFlux of a concentration using weak contributon
Hi,I am solving the advection-diffusion equation of a speceis inside a Domain. Now I want to put a flux of the same species on a boundary using weak contribtion inside that physics. What expression...
View Articletwo way FSI with prescribed displacement causing gaps in mesh
I am experimenting with a very simple two way FSI. A solid square is moved through some air. I place a prescribed displacement on the bottom of the square. What seems to happen is an actual gap in the...
View Articlereducing comsol file size
Hi all, I am trying to reduce the size of my comsol file. I need to define several cut planes and then tell comsol only save the T distribution over these planes (x,y,z,T). is this possible? to define...
View ArticleModelling 'Helix' Turbine- Meshing Problems
Hi All,I'm trying to model an alternative type of turbine, which is a version of vertical axis turbine that is deployed horizontally in a micro hydro electric power setting.I'm relatively new to...
View ArticleSplitting into several domains
The below post is related to an archived discussionHello,I have a rectangular geometry with several channels, which water is supposed to flow through. Other than the channels, the rest of the geometry...
View ArticleStokes Equation
I want to simulate my problem using Stokes equation and convection diffusion equation. I want the Stokes equation to not have any transient term. But the creeping flow module has time dependency, as I...
View Article2D Pipe Flow
I have simulated a stationary 2D pipe flow in a 30 mm X 5 mm rectangular domain using the Creeping flow module to solve the incompressible Navier-Stokes equation. The boundary conditions are no-slip...
View ArticleMaterial properties in flow with a reaction
Currently with our flow design we have designated the inner tubing domain as a user-defined material. This was because you cannot add more than one material to a domain, but we wish to have all...
View ArticleCellular Swelling
Hello,I'm new to COMSOL and was interested in modeling a cell with a cellular membrane domain swelling due to a difference in concentration inside the cell relative to the outside of the cell. This...
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