Time dependent simulation
Hello Ivar, I need a big favor from you. Its a request since my model is giving weird results. I have worked on it but I need to get the physics right. So I decided to try the time dependent study...
View Articlewhy are my solutions the same as initial values?
Hi. I build a 1D time-dependent model (transport of diluted species). using conservative form. convection transport mechanism D=0; u=-k/x^m; (k is a constant) R=0; no flux iniitlal distribution:...
View Articlehow to define Heat source?
Hi, I use COMSOL to simulate a microheater to heat the polymer waveguide on Silicon substrate. The model is 2D. Silicon substrate serve as the heat sink at 25 degrees. When I set the microheater to 300...
View ArticleDifficulties with #985 Peristaltic Pump Model
Hi All (bear with me; I'm new) Working my way through the peristaltic pump tutorial and all has been a-okay thus far but once I get to the plot of the total volume (bottom of pg. 14) when I try to...
View ArticleBackward Problem
Dear Comsol Users, I like to scale a given heatflux distribution to reach a maximum temperature in a domain. If I know the location where I expect this max. temperature, I can do this via a global...
View ArticleOptical coupling between laser wave-guides and optical fiber
Hello Everyone, First of all, I am a beginner to use this software and getting to know this from the tutorials posted. I am trying to model 'Optical coupling between laser wave-guides and optical...
View Articleminimum time value under condition
Hi I have a problem on my simulation I have a time dependent simulation and I want to get the minimum time value when a phenomena occur ( The voltage V raise a value above a certain threshlod) I want...
View Articlemagnetic field gradient in 3D return zero!
Hi everybody If anybody knows that why the gradient of magnetic field in 3D models is always zero? I checked the different methods. for example I wrote d(Bx,x) or different component of B and H. Even...
View ArticleHow to make sure AC/DC and Structural models are coupled? SIMULATION ATTACHED
I'm doing my thesis on the magneto-mechanical coupled analysis. The attached file is only a simple example showing what I want to do about magneto-mechanical coupling. I chose to use the AC/DC model,...
View ArticleUse eigenfrequency found in study 1 as a parameter in study 2
Hello all, My simulation is divided into 2 studies: Study 1: Eigenfrequency (model: solid1) Study 2: Frequency domain (model: solid2) Have you an idea how to use one of the eigenfrequencies found in...
View ArticleInitial Concentration in Reacting Flow in Porous Media
Hello, I need to know if I can add a starting concentration for a variable in the Reacting Flow in Porous Media, that will then change via the Reactions Node. The Initial Values Node does not seem to...
View ArticleSegregated Solver
Hello, I was wondering if someone could perhaps explain to me the nature of the segregated solver so that I may understand it a little more clearly. I have seen other threads discussing this in the...
View ArticleWhile Loops and Converge Criteria for pseudo steady state model
Hello, I am attempting to create a series of simulations whose aim it is to examine the influence of my model's physics on the models geometry. What I have is a vascular geometry , which has a certain...
View ArticleUpdate Interpolation function in each simulation step
Hello Everyone, I am trying to set up a time-dependent simulation in COMSOL v4.3a. It's a structural mechanics model and the material properties are defined by an interpolation function which is read...
View Articlenegative concentrations with high reaction terms in biokinetic models
Hi, I am using a biokinetic model based on the ASM (activated sludge models) to simulate water contaminant removal in a gravel filter. This kind of models consider the degradation of the influent...
View Articlewhat is wrong with the ALE
(all are in the .doc attachment. Thanks) Hi,everyone, I ‘m building a simple model based on the “heat transfer” module and the “ALE” module. The geometry is a simple rectangle. In the heat transfer...
View ArticleConvergence behaviour in a stationary solver
Dear Comsol gurus, I have been dealing with a CFD/transport of diluted species (TDS) simulation for a while and I was hoping you could bring some light to the subject. I am simulating a flow in a micro...
View ArticleTime dependent simulation
Hello Ivar, I need a big favor from you. Its a request since my model is giving weird results. I have worked on it but I need to get the physics right. So I decided to try the time dependent study...
View Articlewhy are my solutions the same as initial values?
Hi. I build a 1D time-dependent model (transport of diluted species). using conservative form. convection transport mechanism D=0; u=-k/x^m; (k is a constant) R=0; no flux iniitlal distribution:...
View Articlehow to define Heat source?
Hi, I use COMSOL to simulate a microheater to heat the polymer waveguide on Silicon substrate. The model is 2D. Silicon substrate serve as the heat sink at 25 degrees. When I set the microheater to 300...
View Article