heat source setting
HI;I have a question that when I using heat transfer in solid and lamina flow model to simulate heating a crucible in a silicon furnace, when I setting the heat souce desity equal:6000W/m^3, the...
View ArticleIndetity pairs should be fixed?
hello I am running a static structural mechanics problem on comsol multiphysics 3.5 . I have a building and i want to see the effect of a seismic load on my structure .. My problem is that the building...
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 ArticleMEMS Microcantilever with electrostatic actuation
Hi I'm new to Comsol and would like to model a mems electrostatic switch. For this I am referring to this example:www.comsol.com/showroom/gallery/444/ I was trying to understand the 3d model provided...
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 ArticlePCF, PML
Hi, I am designing a PCF with hexagonal pattern having five air hole rings. pitch = 1 um. air filling fraction = 0.90 i have used circular PML to get the imaginary part of refractive index. what should...
View ArticleMetal film with subwavelength size hole: Transmmittance and reflectance study
Hi I'm novice in comsol RF simulation. I'm trying to simulate transmittace and reflectance throught metal film with subwavelength size hole. My structure will consists of Air/metal/semiconductor...
View ArticleGain Medium with Circularly polarized light in COMSOL
Dear All COMSOL follows exp(-iwt) modeling in the and hence the absorption of the material is given by imag(permittivity) >0. If I want to simulate a gain medium, is it trivial to replace the...
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 Article"Error: Duplicate variable name."
I am using solid mechanics, electrostatics and moving mesh and I want to perform an Eigenfrequency Study. The solver crashes with an error message:"Error: Duplicate variable name." But I didn't find...
View ArticleHow to pass result from one module in to another module.
HI All I am working in two modules, Structural mechanics and Electrostatics. I want to pass the result of the Structural mechanics module as input in to the Electrostatic module. For example: I want to...
View ArticlePlasticity
Whats the difference between Small Plastic Strain and Large plastic strain? How is a model with contact and friction to simulate? What is important? My models usually have convergence errors when I...
View ArticleHeat Transfer in Solid combined with HT Fluid: Problems
Hi dear members, Please I am working on a heat transfer case where I have to show the heat transfer in the fluid and on the mateial. the first one in fluid is done, but the latter on the solid is...
View Articlethermophoresis effect on particles suspended in air flowing through...
Here, I am using thermophoresis model file for reference in which hydrogen fluid flowing through pipe and particles deflect from their paths dur to heated wall. but, I want to verify thermophoresis...
View ArticleFinding Harmonics of an IDT SAW device
Hello, I have a two-port SAW device and I would like to plot scattering parameters (mainly S12) in a frequency dependent fashion. I was having trouble integrating the RF module, so I initially tried...
View ArticleCalculating contact area
Is there any way to calculate the contact area of a contact pair within COMSOL (ie without having to post-process data in MATLAB, which I have yet to try)? I have tried surface integration and other...
View ArticleUsing geometry values in physics boundary conditions
Hi all, I have tried to look around but have not figured out a way to do this. I would like to use a geometry value (i.e. the surface area of an ellipsoid) to define the flux boundary condition through...
View ArticleHeat conduction in solids - temperature dependent heat transfer coefficient
Hi, I would like to solve a simple heat conduction in solids problem with a temperature-dependent heat transfer coefficient at one of the boundaries h(T) = 1000*(300/T)^1.3 However, the result computed...
View ArticleComsol error
Hai , I am Sathya Priya.. I have few question regarding comsol multiphysics. I am designing a single axis accelerometer in comsol, which has a cantilever attached to the proof mass as a part of my...
View ArticleSimulation Error
Hi there. I am working on effect of AC electrical field on the microelectrode. However, when I tried to compute the study (either by using stationary or frequency domain), I kept getting error message...
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