Why is Storage model in Darcy's Law time dependent?
Dear all, A simple square using Darcys Law. If I use the default "fluid and matrix properties" and make all the material properties as CONSTANTS, the result is static even if I use time dependent...
View ArticleMelting by moving heat source and Fluid flow inside liquid region
Initially, I solved heat equation with phase change module for stationary and moving heat source and able to track the solid and liquid regions and for the next step I would like to simulate fluid flow...
View ArticleProblem with transport of diluted species module
Hello, I'm trying to use the boundary flux variable of the module in other modules, so to specify a flux in another module, the problem comes when I look at the equation of the flux:...
View ArticleHow can I simulate the behaviour of a valve?
I want to set up an open outlet for 0.5 seconds, close it after 1 second and open it again after 1.5 seconds; it's like to alternate an open boundary condition (free flow mass) to an outlet boundary...
View ArticleFree Convection in Reduced Pressure (Air)
Hi All, I am trying to simulate heat transfer in a solid material (by conduction ) located in air where free convection is possible. However, I would like to be able to change the pressure of the air...
View ArticleRecirculation zone estimation
Hello, I am trying to estimate the extend of the recirculation zone in a simple heat exchanger problem. The model is a 2D representation of the hot fluid channel. In this model I concentrate only on...
View Articlefluid flow under deforming elastic membrane
hi i am working on pulsatile fluid flow and willing to reduce pulsations with compliant chamber with elastic membrane. In this geometry, we need to define liquid domain (i.e. where liquid flows inlet,...
View ArticleIterative solver for Forchheimer flow
Dear all, I am relatively new to COMSOL so please bear with me. I have made a simple axysmmetric model with an inlet on the left hand side and an outlet on the right. The flow between the two has to be...
View ArticleImporting a file from AutoCAD to COMSOL
I have created a 3D building model on AutoCAD and wish to import it to COMSOL for CFD analysis. Can I know the process for importing?
View ArticleCoupling Darcy's law with Navier-Stokes equation - convergence problem
Dear Comsol-Community, in the hope that someone of this great community might help me, I will try to explain my current problems with coupling Darcy's law and laminar flow. Basically I want to study...
View ArticleNew to COMSOL. Kindly need assistance in designing a microfluidic model of a...
Hi All. I need some help designing a COMSOL model of a microfluidic channel of rectangular geometry (Length: 28,000 um, Width: 400 um, Height: 100 um). The flow inside is required to be modelled as...
View ArticleWhat actually the initial log lines means?
I found the below lines logged in comsol. Time-Dependent Solver 1 in Solver 1 started at 19-Jan-2016 06:54:18. Time-dependent solver (BDF) Number of degrees of freedom solved for: 346770. Nonsymmetric...
View ArticleFSI - contact pair
Hi! I've got a problem with simulation one-way valve, from model library. I'm using a fsi simulation with hyperelastic material. I want to simulate the same example, but with obstacle. The problem is...
View ArticleSolving laminar flow 3-D problem
Hello. I'm working on a master thesis. For the thesis i'm designing a Comsol model. It represents a 3-D geometry with oxygen flowing in it. Is there anybody who can help me to get the model working? I...
View ArticleMaterial melted in combustion chamber
Dear All I am modelling a combustion Chamber, which contains an inflow and outlow. This means the material enters in solid phase, it warms up and leaves the chamber in liquid phase. I need to have a...
View ArticleSimple 2D Flow Problem but no convergence
Hi All, I am trying to simulate very simple fluid flow with an inlet and outlet boundary conditions but I am having trouble with convergence. For some reason, my result would not converge. I was...
View ArticleHow to use Laminar Flow Pressure results in Solid Mechanics, help?
Hi, I need to use as an input in the Solid Mecanic module the Pressure results from Laminar Flow calculations. Can anyone explain me how to do this? thank you for yor answer. Best regards, Leonardo.
View ArticleMoving Mesh velocity in tpfmm
Hi, I'm wondering how COMSOL calculates the mesh velocity (tpfmm.x_free ) in the tpfmm module, as I define a flux in fluid-fluid interface I want to know it because the velocity is very slow and need...
View ArticleHeat transfer along open/screen interval of a borehole located in a porous...
Hi everyone, I am trying to model heat and mass transfer in a pipe flow that is opened along two screen intervals (see attached file). For that purpose I use the non-isothermal pipe-flow interface...
View Articlecontrolling the flow from inlet with respect to time
I'm doing droplet separation in comsol and I want to know is it possible to control the flow rate in an inlet at the specific time which means I need to start the flow (say,Air) at 40ms.
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