Shear stress boundary condition
Hi, I am trying to solve a simple fluid flow problem. It involves marangoni effect. But, I want to make it simple and apply shear stress as the boundary condition, instead of solving coupled thermal...
View ArticleParticles orientation in a fluid.
Hello Comsol user, I wanted to test the following experiment: A fluid flowing in a pipe containing some elliptical particles. The orientation of the particles in the fluid will than be dependent on...
View Articlecalculate the concentration of oxygen through porous support
Hi, It is the first time I used Comsol, my project consist in the measure of gas permeability through porous support. Within Comsol I have already create the plan geometry and put the boundary and area...
View Articletimestep in stationary study?
I am modeling laminar flow at steady-state. Error message: Undefined variable. - Variable: timestep - Geometry: geom1 - Domain: 2 Failed to evaluate expression. - Expression:...
View ArticleUsing COMSOL for Meshing and Solving of Specific Element
Dear Colleagues, I am new to COMSOL and have very basic question. I am working of flow and stress in porous media. As part of my research, I will develop an element with specific degree of freedoms at...
View ArticleHeat flux through a boundary
Hi guys Ive been roughly following this tutorial to model a heat exchanger www.youtube.com/watch?v=7U5ue03K7gQ Using different geometry and BC's It uses the expression intop1(nitf.qwf_u) to calculate...
View ArticleHow to define a mixture of two miscible liquids at the inlet?
Hello, I have a question about how to define a mixture of two miscible liquids (for instance water and ethanol) at the inlet. My 2D geometry is as follows: I have two parallel rectangles (representing...
View ArticleNavier stokes in COMSOL
Hello everyone, I am trying to find out how the compressible NS equations are solved in COMSOL. There are ample explanations of how this is achieved in fluent. Some of the things I am interested in...
View ArticleInflow heat flux issue
Hi everyone, It looks like I'm having a little issue while using the inflow heat flux condition in the heat transfer module. I'm studying a boiler where a burner in the middle is producing 24kW. Then...
View ArticleUnable to evaluate speed and pressure in a solid?
Hi everyone, I'm doing a simulation of a boiler using both the heat transfer module and the CFD module. The simulation always stops because the solver is not able to compute the value of pressure and...
View Articlescaling of variables
What is scaling of variables and how does this influence the final solution? What should be chosen for scaling of variables from "manual, initial value based, automatic, none"? Thanks for the help....
View ArticleHow to set convergence criteria?
Hi everyone, I'm working with the CFD and heat transfer modules and I'm not able to figure out how to set the convergence crtieria. I'm performing a stationary study with a relative tolerance of 0.001...
View ArticleModelling a plasma gasifier
Dear, For my master's thesis I am modelling a plasma gasifier, without using the plasma module, but only - the heat transfer module (fluid and solid) - Fluid flow Laminar - Radiation in participating...
View Articlecoupling fluid flow with acoustics
Hi, everyone I would like to know what velocities of a fluid are produced by the vibration of a probe submerged in it. I have already done transient acoustic modeling, where the pressure distributions...
View ArticleDrift Diffusion and Heavy species transport coupling
Hello I am modelling an AC-DBD plasma actuator (model is attached). I have modeled my time-dependent ac circuit and have proceeded to include the drift diffusion model and heavy species transport...
View Articletransformer simulation with AC/DC, HEAT TRANSFER
Hi everyone, I would like to simulate a three phase transformer in 3D with more module in the same time. The aim of my model is seeing the effect of the magnetic field (eddy current, leakage flux) for...
View ArticleMobilization of vehicles during a flood
Hi, everyone I would to use Comsol software but i like to know if i can simulate the motion of a car, initially stops, during a flood event. That is if I can simulate the motion of a solid sweep away...
View ArticleTIC Nozzle Simulation
Hi, I am a starter here, and trying to simulate the Nozzle flow by the new feature of this edition, High Mach Number Physics. I already came up with the contour of it and import it into the comsol. I...
View ArticleDrift Diffusion and Heavy species transport coupling
Hello I am modelling an AC-DBD plasma actuator (model is attached). I have modeled my time-dependent ac circuit and have proceeded to include the drift diffusion model and heavy species transport...
View Articleroot-mean-square , rms
hi,how i can get standard deviation(root-mean-square,r.m.s.) from lift coefficient for a cylinder in fsi modulus ?(please explain in details)
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