Vibrations: Eigen Frequency Analysis
I understand that Eigenvalue=(Eigenfrequency)^2 , where eigenfrequency is is in Rad/second i.e angular velocity. To get cyclic frequency we divide eigenfrequency by 2 PI i.e. f (Hz)= eigenfrequency/2...
View ArticleImprovements to Comsol Multiphysics - suggestions for the software and...
I love Comsol alot. Being a programmer for years, Comsol is like a programming language for Multiphysics and Math. Nevertheless, there are some points that I would like to see them taken care of. I...
View ArticleCOMSOL Vs ANSYS
Hi there. Can anyone tell me what is the strong and weak point for both COMSOL and ANSYS respectively?
View ArticleTemperature change from expansion of air
I am trying to model the flow fields of a fluid (air) traveling through an orifice. I have a working model that works great using only the laminar flow module. However, the viscosity of the fluid is...
View ArticleWhy does my S11 parameter change when adding a 2nd inactive port?
When looking at off-normal reflection from a periodic structure, my S11 results change when I add a second, unexcited periodic port (S2x). My first periodic port is sending a TM mode in Hy, with...
View ArticleOpening older files
Hi, I just upgraded my mac OS and the admin installed a newer version of COMSOL (4.4). I was wondering if I still can open my simulations made in older version of COMSOL. I think I had 4.2 or 4.3 .....
View ArticleAC/DC , Single / Multi-turn / Group coil domains !
Dear COMSOLer's ! I am relatively new to COMSOL and i am still trying to get things understood right , i still have a lot of questions and i will be really grateful if someone could help ! what is the...
View ArticleCapacitance Calculation with prescribed acceleration boundary condition
Dear All I am trying to simulate a capacitance accelerometer in electromechanics module. I started with a basic 2D model. I am trying the to calculate Capacitance Vs Acceleration. I feel that the...
View ArticleMicrowave heting
Hi, Everyone I am using module of microwave heating, my problem is that, I have an X-band Rectangular Waveguide in which i placed a dielectric block (Refer to module = RF Heating Model ID: 6078) . Now...
View ArticleSelecting an appropriate time stepping for heat transfer transient analysis
Hi everyone, I am currently solving heat transfer problems using transient analysis, but I am having doubts about selecting the correct time steps for my solver. What I am interested in is to run the...
View ArticleMoving Mesh: Linear front in circle
Hi all, when i am using a moving mesh in a rectangle it works fine. But at the moment i am trying to use a moving mesh/deform geometry in this way: a linear boundary should move through a circle. But...
View ArticleSimulation not terminating once error is smaller than defined tolerance
When using comsol 4.4 (and using segregated groups) to solve a problem involving natural convection, I am noticing that simulations do not stop even when the error in each group is below the defined...
View ArticleUsing a function as an input to simulate turn-on turn-off sequence
I'm using the Joule Heating module and I'm modeling a simple wire heater that heats up when I run a current trough it. I want to see how the temperature of the heater decays as a function of time in...
View ArticleTemperatures calculated but thermal expansion calculation is missing ?
I generate a quite simple 3-D model: A cylinder made of copper with a radius of 0.2m and a height of 0.5m and heated at its mantle with a total energy of 1000 Watts for one hour. Within this cylinder...
View ArticleLearn more about COMSOL core functionality
Hello everyone, You might want to take a moment and read a collection of fun and informative blog posts about core functionality written by the COMSOL technical staff...
View ArticleError during multiphsics
Hi.. We are try to design saw delay line gas sensor, during the simulation we got error as- Fail to find destination boundaries or destination selection empty please help us to sort out this error. --...
View ArticleHeat Transfer rate with electric Current
Dear All, I want to see the heat transfer characteristics in a steel tube using water (Laminar Flow). Please advise how can i insert electrodes in the water. I mean modelling and calculating Heat...
View ArticleShift in variable
Hi everyone, I am modeling one ode which looks something like this u``=function(u(x+1),u(x),u(x-1)), where u`` is derivative of u with respect to x. I dont understand how to specify u(x+1) and u(x-1)...
View Articleheat transfer in fluids with phase change
Hi I have a heating element with defined power in a kettle with water. Any ideas how to model time dependent heat transfer ? Thanks David
View Articlepositive_column_1d example ...
Hi, In positive_column_1d example in Plasma Module : I receive the following error massage, when I increase applied voltage V0 from 100 V to e.g 1000 V : Repeated error test failures. May have reached...
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