Non-newtonian Flow
I am simulating a chute flow. My geometry is a rectangular box. There is an inlet and outlet and other walls are fixed. In inlet I am giving velocity inlet conditions and at the outlet I am giving...
View Articlemodelling a vertically moving plate with free horizontal rotation
May I ask someone to advise me how would I model a rectangual plate with prescribed vertical translational motion capable of free rotation along horizontal plane. Plz see the image attached. Any help...
View ArticleHeat flux boundary condition - Weird generation of heat
Hello everyone! I have a 3D model of a conjugate heat transfer problem, where i am simulating a flow inside of a channel. I'm trying to simulate the behavior of my problem has real has possible and my...
View ArticleFailed to Evaluate Variable Rho
Hi, I'm modeling a 3-layer device (fluid flow/porous membrane/fluid flow) with Free and Porous Media Flow physics in version 4.2a. I'm trying to add the effects of gravity to my model (I've already...
View ArticleBoundary Stress
Dear all, i have a problem. I try to simulate a fluid flow effected by a boundary stress on a key hole. See attached mph-file. With a very big mesh, comsol solve the problem. But with a smaller mesh,...
View ArticleMass flow rate vs temperature.
Hi, I used Comsol to model a really simple problem. A pipe with 50mm diameter and 25m long with an inlet temperature of 20°C and 0.5kg/s of mass flow rate. Also, the pipe´s wall temperature was 150°C....
View ArticleRotation of 3D geometry taking too long time to compute
I am using the rotating machinery laminar flow physics. I am trying to solve with time dependent study. Every time after computing 7% or 4% it hangs up and continues doing iterations upto 2000 and...
View ArticleFSI Fixed Geometry
I am trying to model an FSI problem with the FSI Fixed Geometry physics. I don't completely understand how this physics works, but I am having a problem that I think is related. I have a boundary...
View ArticleProblem with Transport of diluted species concentration calculation
Hello, I am trying to model a system which is formed by four inputs channels, for ech one of them water is flowing. Besides it is another input, a central one, for which flows an organic material. I´m...
View Articlesome questions about surface tension between deform solid and liquid
I want to define the surface tension between solid and liquid, but I found there is no such defination in fsi. But there is defination in tpf. I wonder if I can combine two module to introduce surface...
View ArticleFluid with viscosity as a function of Pressure
my function of viscosity is mu=((0.3839*(p)/spf.sr)*(1-exp(-m*spf.sr))+((0.241*0.0001*(p))/(spf.sr*0.001+0.3*((p)/2600)^0.5))) where p=pressure, m=parameter and spf.sr=shear rate Gives an error of...
View ArticlePromblem with defining the initial values!
Hi every one I defined a induction heating model on comsol 5.1 as a frequency stationary study. As you may know, with this module you will get the heat conduction in soilds as well. in the next step,...
View ArticleVolume Force
Hello everyone, I am trying to model free convection in air and water using the Boussinesq approximation. I use a volume force but I hesitate in the right value of this term. I have seen a lot of...
View Article3D modelling of ICP torch
Hello! I'm trying to modelling 3d ICP torch. But i have problem with Magnetic Field. I don't understand how can choose input power? I see only current and voltage.Also, what is the difference between...
View ArticleFailed to find a solution. System matrix is zero. Returned solution is not...
I am trying to solve 2 coupled ODEs and am using the coefficient form PDE module to solve it. I have zeroed out the coefficients of the terms with time derivative. Btw this is a 1D problem where the...
View ArticleSolid and Fluid motion with eigenfrequency study
Hello, I made a very simple geometry in 2D, such as the cross-section of a microcapillary. I want to find some eigenfrequency which can make a few modes on a microcapillary. So, for the shell I used...
View ArticleModel convergence issue
Hello everyone I am conducting a time dependent study. My model converges for smaller time scales viz range(10^-12,10^-6,1.1354e-5) . However, when I run the study for a larger range, which is...
View ArticleDeformed geometry
Hello, I am trying to create a two-phase flow simulation where the fluid is in a cavity and one of the walls of that cavity moves. The wall moves outwards and so air needs to be pulled in at an inlet...
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 ArticleComputation of heat per unit volume, BUBBLY FLOW, HEAT TRANSFER
I have a problem with phase change. I have modelled it using bf (turbulent bubbly flow) and ht (heat transfer). Under bubbly flow is the exciting part: Mass Transfer. Since this is in a vessel which is...
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