Problem of the boundary condition at bubble surface
Hi， I'm now trying to use N-S and continuity equations to calculate the drag cofficient of spherical bubbles. I use the PDE and 2D axisymmetric model module to simulate. when setting the boundary...
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 ArticleInternal fluid-fluid boundary issue
Hello all, Inexperienced comsol user here. So I have a 3-d model of a cylinder. In the lower half of the cylinder there is water while in the upper we have air. Air is rotating around the cylinder due...
View ArticleHow to stop flow in simple microfluidic gradient generator and use time...
Hello, I am trying to model a microfluidic gradient generator, like this:www.elveflow.com/wp-content/ga...t-on-a-microfluidic-chip-a.png While it was not difficult to put together the stationary study...
View ArticleSolution for Time-dependent Solver - not working properly
Hi All, I seem to be having a difficult time solving a time dependent solution for any of my darcy flow porous media models. The problem I am encountering is that all the time solutions that are stored...
View ArticleWhich BC needed?
Hey there, I am quite new to comsol so maybe there is an easy way to do it. I have a pipe with an internal helix structure which is repeated after a 180° twist. I want to use this symmetry to save...
View ArticleQuestions about "bouyancy water" model
Hi, guys I have been learning the "bouyancy water" model of the "model libraries" these days , it's a simple model——temperature differential produces density variation that drives the bouyancy flow in...
View ArticleConjugated heat transfer - no convergence
Hello! I am modelling a heat transfer problem coupled with convection in a fluid using the conjugated heat transfer module. My material properties are temperature dependent. The model is time...
View ArticleAdditional dependent variable laminar flow
Hello Comsol Community, I try to simulate a laminar airflow in a rectangular channel. The air enters the domain at the bottom of the channel and leaves it at a lateral wall. In this simulation I want...
View ArticleNavier-Stokes Simulation using General Form PDE: The Continuity Equation
Greetings all. I am working to solve a standard fluid flow problem (e.g. flow in a pipe as a start) using the General Form PDE interfaces instead of the Fluid Flow built in GUI. I am able to define a...
View Articlesolve a system of PDEs (study a bubble pump)
hi can some one help me to solve a system of différential equation for a problem of di-phasic flow , the model adapted id drift model , you found in attachement the system of equation. thank you for...
View Articlecoupling acoustic with fluid flow
hi, I need to use "acoustic" and "fluid flow" modules to solve my problem.the only common dependent variable in this two is pressure .i want to couple this two to reach pressure field.do you know how i...
View ArticleWeak contribution to levelset interface
Dear all, I would like to add a weak contribution (for surface tension) to a moving levelset interface for the following application: I want to model a fluid with a free surface, on which there should...
View Articleheat transfer and fluid flow in a tube ( heat & velocity problems )
Hi guys, I am working on a flow of helium in a rectangular tube and this tube is subjected to heat flux, the problem here when the results come out the temperature distribution in about 7*10^5 degree...
View ArticleNeed help with a degradable polymer simulation
Greetings I'm trying to build a model of drug release from a bio material. The drug is carmustine which is released from the biodegradable polymer Gliadel wafer, which is implanted in the cavity...
View ArticleCFD,high mach flow
hi , i want to simulate a blunt body in high mach flow condition .high mach flow k-epsilon module used to simulate .but when inlet speed exceed from .8 mach number ,it give an error , how can i fix...
View ArticleHeat Convection with Air and Water
Hello everybody, im trying to do a simulation like in the picture below. What i expect to see is natural convetion in the Air and Fluid based on the density change in the material. I already did some...
View ArticleCFD of air filter inside room (URGENT)
I am trying to model the air flow of a room with a filter box inside the room that has an inlet and outlet to it. However, the only information I have been able to find online to help me are vents that...
View ArticleStreamlines
Hi All, I am working on a micropump and trying to have a plot of the flow. How can I generate a plot just like the attached picture? I tried streamlines, but I could not get the direction of the...
View ArticlePeriodic Heat Exchanger and Thermal Stress Simulations
Hello everybody, I have 2 different Problems, that i want to address and hope to get some hints on how to solve it. 1: Periodic Heat Exchanger: I want to model a Heat exchanger where the fluid flows...
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