COMSOL 4.0a : how to set maximum Java heap size??
Hi, I have problem to set comsol java heap. In v3.5a, I know I can modify java heap in comsol.opts. But in v4.0a, I can't find the comsol.opts, and I have no idea about setting the java heap. Please...
View ArticleHagen–Poiseuille flow
I would like to use Comsol for a microfluidics project I'm working on. As this is my first time working with Comsol I am trying to simulate a simple problem to compare the simulation with analytical...
View Articlepartical tracing never works
hi i cant get particle tracing to work help pls. i have a simple 2d example with a rectangular with an electric field on it. the particle tracing modul doesnt show any interaction between the particles...
View Articlesinusoidal voltage to time dependent solver
I am trying to apply sinusoidal voltage to a model with time dependent solver. I apply the voltage based on a function but it doesn't show anything. the model is attached. thanks
View ArticleCement flowing around funky 3D shape and displacing mud
Hi, I have an interesting fluids problem. 3D object in a snug fit inside a water filled tube. Pump heavy cement in one end, will it displace all of the water as it flows around the object or leave some...
View ArticleStructural Mechanics Equation System
I am trying to understand how my structural mechanics model is computing its solution. The model solves and gives me a reasonable solution. However, I don't understand how it is arriving at its answer....
View ArticleHelp solving nonlinear 1D diffusion equation
Hi All, I need to solve the following 1D diffusion equation on domain x=[0,0.4] between time t=[0,2]: w(u) du/dt = d^2u/dx^2 where w(u) = 1+184/u*(-1/log(u))^(4/3) subject to the initial condition...
View ArticleHeat Source Expanding with time!
I have a model for EDM process in which I need to put an heat source which would be expanding with time. But it shows error if I give time dependent position of a point under boundary conditions. Laser...
View Articlescript for exporting deformed geom from livlink matlab ?
Hi all, In GUI, I could remesh the deformed configuration from the results dataset, and from there i could export to a new geometry (xx.mphbin). But how can i do the same from matlab livelink ? I...
View Articlehow to calculate the parameter values of a curve edge in mesh file
Hi guys, I exported a mesh file from comsol. Can anyone tell me how to calculate the parameter values of a curve edge at two endpoints, respectively? Below is the mesh data of a circle: # Major &...
View ArticleProblem on Analytic function
I want to define analytic function E, which is a function to time, t, but when I want to plot out E(t), there is always a error, which is attached. Who can help me figure out what is the problem? t...
View ArticleComsol 4.3a Memory problem -- not using enough RAM
Hello everyone, Usually the complain is that Comsol is using too much memory, but in my case its other way round. I have a really nice machine in the lab with windows 8 server. I have Comsol version...
View ArticleHow to calculate curve parameter
Hi, guys, Given a curve and a set of points on this curve, how to calculate the curve parameter value at each point? I am struggling on this problem for a few days. I will appreciate it if someone can...
View ArticleHeat Transfer Problem
Hi everyone, I found my heat transfer problem is taking too long to solve even in stationary. The problem is about a pair of thin pipes embedded in soil. pipe diameter 25mm, 20m long each. There is...
View ArticleProblem with insulation...
While using the Non-Isothermal Flow (nitf) and Heat Transfer in Solids (ht), I am facing problem with insulation being allocated to the faces that are not insulated. I suppose that I am not getting...
View ArticleHow to enter the temperature that varies with time??
Due to the variation in air velocity, the external temperature varies with time. Can I know how can I input the values using an equation or an excel sheet??
View Articlewidth of PML
What will be the width of the PML( circular) to determine the confinement loss in hexagonal pcf. Regards Md. Samiul Habib
View ArticleParallel computing MatLab Comsol
Hi, I am using Comsol 4.3 with Livelink for Matlab. I run an optimization code in Matlab where i call Comsol to perform frequency response simulations. Now i would like to start two parallel frequency...
View ArticleMie scattering in 4.3
Hello, I have already seen some discussion about mid scattering of a gold nanosphere. But I the discussions I have consulted, no one has yet implemented a mie scattering program in Comsol 4.2 or 4.3...
View Articlegive specific values for every mesh point of a boundary as boundary condition
hey everybody, is it possibly to give different values for all points of the mesh on the boundary, respectively? for example, just a vector containing as many values as i have boundary mesh points, or...
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