Meaning of "node" vs. "vertex" vs. "degree of freedom" for linear finite...
Hi there, can anybody tell me what COMSOL means by the word "node" in contrast to "vertex" or "degree of freedom" when it comes to the discretization? I have...
View ArticleTime Dependent Study of an Airfoil- Lift Coefficient
Hi, I am trying to learn how to calculation the lift and drag coefficient of an airfoil running a time-dependent study. Below are the boundary conditions. Re ~2000 Inlet- Inlet U*step1(t[1/s]) Top and...
View ArticleHelp variables in weak form
Hi, I'm wondering how to insert a help variable in the weak form. I am solving for three variables u1, u2 and u3. However, my weak form integrand is a complicated function of these variables. So I...
View Articlemodifying Vibrating Beam in Fluid Flow
I am trying to modify Vibrating Beam in Fluid Flow, which is given a example of FSI on this site. what I want to change is the condition of the cylinder. In this example, the cylinder is fixed,...
View Articlecan we bound a dependant variable?
Hello, I use laminar flow plus adding a convection-diffusion equation as a pde one to NV and continuity equations(time- dependant) to solve my simulation. The problem that I have is that the magnitude...
View Articlemixing of fluids!!
hii!! I am using this software for the first time and i need help... I am using version 4.0a.. i want to know how to mix 2 liquids (blood and glucose) with different properties in a cylinder which is...
View ArticleMake my model infinite at one direction
In order to make my block having an infinite length in x-direction (as it is a stripe of graphene and extends along its length to infinity) Should I use some specific Boundary Condition??
View ArticleSettings for simulating static or rf field between metallic contacts
Hi, I'm a new Comsol user and I'm interested to simulate the 2d field between two electrodes on a substrate. The electrodes can work at low but also at high frequencies. I've been able to draw the...
View ArticleFlow in a pipe with a very large aspect ratio
I'm trying to solve what should be a very simple problem as part of a larger project I'm working on. It's just laminar flow in a pipe of length 14,000 feet and radius 0.04 feet. I'm just trying to find...
View ArticleMessage:
What does this message mean: Parametric solver does not support geometry and mesh dependent parameters? It solved me things but not sure if it is correct.
View ArticleAssign number of processors to a Comsol server
Hi, the option -np sets the maximum number of processors that Comsol is allowed to use. When Comsol is started in server mode this option seems to be ignored. For example Comsol server is started...
View ArticleModulo function for making pulse train.
Hi, Trying to make a pulse train by combining the heaviside function with the modulo function, as described in a previous post. The heaviside works fine for one pulse: (flc2hs(5- t),1) But when I...
View ArticleCreate Equation
Hi In COMSOL it's given the wave equation (file 1) - PDE waeq but I want to use other form of this equation (see file 2) this means I need to create or modify the equation in the COMSOL how can I do that?
View ArticleFluid flow channel in cantilever beam
Hello, My model is the following: a cantilever beam has one longitudinal channel containing a fluid flow. My goal is to find the effects of the fluid flow (viscosity, velocity, size of the channel) on...
View ArticleMultiple concentration step function
Hi, Have a great day. I am a new user of comsol 3.5 version, currently, I am working with chronoamperometry and I am trying to simulate that one using comsol by multiple concentration step functions....
View Articlethe free vibration of the cantilever
Hi everyone: The initial displacement D=1.05mm, is placed on the end of the cantilever beam, to solve the velocity response of the beam end. First, I select space dimension 2D, and add physics Beam,...
View ArticleMaxwell Stress Tensor
Hello all, I'm new to Comsol and Im having a little difficulty getting my head around how the Maxwell Stress Tensor operates. I understand its operation when applied to parallel wires (Like in the...
View ArticleModeling a water turbine using actuator disc theory
Hello, I'm trying to model the flow in a (simplified) tidal channel. For now there is one turbine placed in the channels (this might be extended to two or more). With this model I hope to study the...
View ArticleElectrostatics using deformed result of solid mechanics
Hi, I am new to COMSOL, using version 4.1 to simulate a flexible capacitor. The goal is to have the geometry deformed using a Solid Mechanics simulation (which I have done) then simulate the behaviour...
View ArticleLaminar inflow into a turbulent domain
I have a 3D geometry in which turbulent flow develops downstream, but the inlet to the domain is a pipe that has laminar inflow. The turbulence physics interfaces do not have a laminar inflow boundary...
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