Prolonged error with "Last Time Step Not Converged"
Dear sir, We were trying out "PIPE FLOW MODULE" as you have suggested. And thanks for the advice, as it has reduced the number of mesh elements to a larger extent. But, we were getting a consistent...
View ArticleHow can I find the flow velocity of a specific coordinate point
Dear all, I would like to ask how can I find the flow velocity of a specific point (x=105, y=2.5) in my channel (it is shown in the picture). In the graph, if I click at any random point I got 3...
View ArticleAutomatically parameter increasing
Dear friends, I have a simple 2D rectangular model, I want to measure some acoustic properties in my desired frequency range, for specific height of model it's easy, but I want to check a range of...
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 Article"Reinitializing GUI" for a long time
Hi, when I solve a PDE, it takes a lot of time. I closed the programme with task manager of windows. When I reopen the file, the programme is "reinitializing GUI" . I wait for almost an hour and...
View ArticleSolve PDE on 1D domain?
Hy guys, I have a problem with solving a PDE based model defined by me, it is not a default template in COMSOL. My problem is that the equation is solved for the time domain, but not for the geometry...
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 ArticleHow to combine the Frequency Domain and Coil Current Calculation
Hello everyone, i´m trying to simulate an numerical coil with alternating current. The coil is built with the "Multi-Turn Coil Domain". My coil type is numeric wich requires an additional "Coil Current...
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 Articlehow to simulate a permanent magnet with vertical movement toward a coil ?
Hello everybody, i want to simulate a permanent magnet with vertical movement toward a coil i've used magnetostatics and moving mesh in comsol 3.5 i defined a constant Br(remanent flux) and a...
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 ArticleCOMSOL in parallel mode: a speedup of 20% using 4 cores?
Hello everyone, I have performed the following experiment. Using the command -np #cores, I have forced COMSOL Multiphysics to use 1, 2, 4 or 8 of the available cores on my computer. I also used the...
View ArticleJava Runtime Environment error
Getting following error, A fatal error has been detected by the Java Runtime Environment: # # SIGSEGV (0xb) at pc=0x0000003da3efbc6c, pid=6909, tid=46912497239488 # # JRE version: 6.0_20-b02 # Java VM:...
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 ArticlePiezoresistive modeling
Hello all I want to simulate a piezoresistive beam with Comsol. I was looking to find an example of piezoresistive modeling to find out what module they usually use and how are the settings but i...
View ArticleError: 7161 The mass matrix is zero - resolve
Respected sir/ma'am, I am trying to simulate a Nano ElectroMechanical Switch(NEMS) using the following modules:a)solid, stress-strain, b) Moving Mesh, and c)Electrostatics. When i run the solver, it...
View ArticleProlonged error with "Last Time Step Not Converged"
Dear sir, We were trying out "PIPE FLOW MODULE" as you have suggested. And thanks for the advice, as it has reduced the number of mesh elements to a larger extent. But, we were getting a consistent...
View ArticleHow can I find the flow velocity of a specific coordinate point
Dear all, I would like to ask how can I find the flow velocity of a specific point (x=105, y=2.5) in my channel (it is shown in the picture). In the graph, if I click at any random point I got 3...
View ArticleAutomatically parameter increasing
Dear friends, I have a simple 2D rectangular model, I want to measure some acoustic properties in my desired frequency range, for specific height of model it's easy, but I want to check a range of...
View Article