Heat Transfer
Actually, I need to give boundary condition to one of the part of my system. At that part, I will use cryocooler of capacity 1 W at 4.2 K, how can I give this boundary condition to particular part. My...
View Articleinitial Values of Variables Solved For
Hi, I have someting to know. As you know, the initial condition set is as follows: initial Values of Variables Solved For Method: initial expression, Solution Solution: Zero, Solver1, Solver2 in...
View ArticleElectromechanics in COMSOL
Hi, I am a student and I have just started using COMSOL. I would like to find out the displacement of a cantilever beam (2-DIMENSIONAL) due to electrostatic force created when 10V of voltage is applied...
View Articleslab-waveguide simulation / scattering losses
Hello, I'm attempting to simulate a simple slab waveguide (see attached). The waveguide has a core of n=1.5 surrounded by air (n=1) above and below. This design is surrounded by PML rectangles. The...
View ArticleSome problems of Bandgap Analysis of Photonic Crystal (ver 3.5)
Hello All, I am trying to run the built-in model of Bandgap Analysis in ver 3.5. But I got some problem: Error: 6170 Failed to evaluate variable. - Variable: lambda - Global scope Failed to evaluate...
View ArticleHigh Viscosity in Two Phase Flow
Hi, I have constructed a two-phase flow model, using the "Droplet Breakup in a T-Junction" model in the gallery. I managed to compute the default model successfully. However, when I change the...
View ArticleHow to Improve Convergence in Natural Convection
I am wondering how I can improve convergence in my natural convection model. It is a simple model; an isothermal aluminum plate in water. The model starts out fine but as the run continues (transient...
View Articleintegral
hi do you know if it possible to calculate this integral in comsol (attach file) ? thanks
View ArticleSurge impedance of transmission tower
Hi everyone. I am trying to model an overhead line system, in which the transmission tower should be defined as a surge impedance. I expect the wave will go down the transmission tower and get...
View ArticleStationary / time dependent solution differs
Hello everyone, my model is a U-shaped pipe in a concrete block. Cold water (1°C) flows through the pipe and the warmer concrete (11°C) surrounding it warms up the water inside the pipe. I used the...
View ArticleCooling Towers
Can we input humidity for simulating cooling tower on COMSOL 4.3a? Can you help me with amy examples, if any??
View ArticleDisplacement computation
hi, i hv designed a nanotube based pressure sensor, am getting some displacement values for pressure applied on nanotube boundaries but how can i know whether the result i am getting is right or...
View Articlethermal model
Hi everyone, I am working on a thermal model and used conjugate heat transfer for simulation. My problem is when i want to calculate the thermal efficiency of the flowing fluid (cooling) by identifying...
View ArticleSetting up a previously solved physics as an initial condition for a second...
I am new to COMSOL 4.3a and I have what seems to be a simple dilemma, but I can't figure it out. I have a model incorporating three different physics. I want to run COMSOL to solve for the first...
View ArticleSetting up solver loop for 2 physics.
Hi, I have a problem that involves EM wave (frequency around 10^14 Hz) and mechanical movement (frequency 10^6 - 10^8 Hz). Basically the EM wave will give a force on the structure, and the force...
View ArticleHow to define Function in Definitions / Variables.
I'm currently working on electrical simulation using AC/DC module. I define nonlinear electric conductivity for zinc oxide material using following function(ZnO) in subdomain settings, but it shown...
View ArticleFixing an Object to a Set Position, Mises Force, Fluid Dynamics
Hello, I am trying to design a 2D microfluidic channel using COMSOL Multiphysics 3.2b. Inside of the channel, I want to fix an object and use COMSOL to calculate the magnitude of the von Mises stress...
View ArticleSetting up solver loop for 2 physics.
Hi, I have a problem that involves EM wave (frequency around 10^14 Hz) and mechanical movement (frequency 10^6 - 10^8 Hz). Basically the EM wave will give a force on the structure, and the force...
View Articleslab-waveguide simulation / scattering losses
Hello, I'm attempting to simulate a simple slab waveguide (see attached). The waveguide has a core of n=1.5 surrounded by air (n=1) above and below. This design is surrounded by PML rectangles. The...
View ArticleSome problems of Bandgap Analysis of Photonic Crystal (ver 3.5)
Hello All, I am trying to run the built-in model of Bandgap Analysis in ver 3.5. But I got some problem: Error: 6170 Failed to evaluate variable. - Variable: lambda - Global scope Failed to evaluate...
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