Is My Laptop Causing Memory Issues in COMSOL Multiphysics Simulations?

  • Thread starter Thread starter labd0001
  • Start date Start date
  • Tags Tags
    Comsol
AI Thread Summary
The user is experiencing memory issues while using COMSOL Multiphysics to model an eddy current sensor, specifically when meshing a plate with a small size and required mesh density. The laptop's specifications, including a 1.5 GHz processor and 1.2 GB RAM, are likely inadequate for handling the large number of elements required for the simulation. Recommendations include reducing the mesh size in critical areas while using larger elements elsewhere, adjusting the element order, and utilizing COMSOL's mesh density options. Additionally, employing mapped meshing and interactive meshing tools can help manage element numbers effectively. Proper mesh management is crucial to avoid memory issues and ensure successful simulations.
labd0001
Messages
9
Reaction score
0
Hello,

I m a student using COMSOL Multiphysics. I have to admit that I am new to this software but it is giving me loads of problems. I am trying to model an eddy current sensor by modelling the coil and a plate (mild steel). The size of the plate is 17mmx17mmx3mm but I had no problem with the geometry.
The skin depth at 100khz is 0.1mm and therefore the mesh size has to be at least 0.05mm. Unfortunately when I mesh the plate, a warning is popping up stating that it is out of memory. I am using a 1.5ghz processor(intel) and 1.2G ram. do you think that the problem is the laptop?

Any replies are greatly appreciated
thanks
 
Engineering news on Phys.org
The mesh size only has to be small in the vicinity of the surface effect. Meshing the entire part using tiny elements is a waste of memory and WAY overkill. I estimate that if you use 0.05mm elements across the entire part, you'll end up with a mesh of about 7 million elements- far outside the capability of a standard laptop or desktop computer. You'll probably want to keep your model down to 100,000 elements or so to ensure it solves in a reasonable amount of time and doesn't run out of memory.

I would recommend resizing the mesh so that the elements are small within the surface phenomenon's region, and you can use larger elements in the middle of the part.
 
Also, comsol by default typically uses higher order elements --> reduce the order. Partition the model appropriately if possible to enable higher mesh gradients. Use the comsol's mesh density options for point/boundary/subdomain. If it still presents problems, try the mapped meshing and interactive meshing tools to accurately specify element numbers at critical areas.

Also, it may be an option to do opposite what suggested at first and use "much higher" order elements and model larger areas with "a couple" of elements still with fair accuracy due to the complexity of the test/interpolation functions. In some cases yields best accuracy with fewest dof.
 
Hi all, I have a question. So from the derivation of the Isentropic process relationship PV^gamma = constant, there is a step dW = PdV, which can only be said for quasi-equilibrium (or reversible) processes. As such I believe PV^gamma = constant (and the family of equations) should not be applicable to just adiabatic processes? Ie, it should be applicable only for adiabatic + reversible = isentropic processes? However, I've seen couple of online notes/books, and...
I have an engine that uses a dry sump oiling system. The oil collection pan has three AN fittings to use for scavenging. Two of the fittings are approximately on the same level, the third is about 1/2 to 3/4 inch higher than the other two. The system ran for years with no problem using a three stage pump (one pressure and two scavenge stages). The two scavenge stages were connected at times to any two of the three AN fittings on the tank. Recently I tried an upgrade to a four stage pump...
Back
Top