Search found 107 matches

by mika
Today, 18:52
Forum: ElmerSolver
Topic: 2d simulation of acoustic wave propagation
Replies: 38
Views: 769

Re: 2d simulation of acoustic wave propagation

Do you have some explicit mathematical formula how the values of phases are generated?
by mika
Today, 12:23
Forum: ElmerSolver
Topic: 2d simulation of acoustic wave propagation
Replies: 38
Views: 769

Re: 2d simulation of acoustic wave propagation

It seems to me that some facts about the model may have been misunderstood. Since the problem relates to sound, the wave motion is longitudinal so that the field variations are in the same direction as the direction of the wave propagation. As the solution (pressure) is not a vector, no direction is...
by mika
Yesterday, 10:09
Forum: ElmerSolver
Topic: 2d simulation of acoustic wave propagation
Replies: 38
Views: 769

Re: 2d simulation of acoustic wave propagation

I don't still understand the purpose of the term k*y in the underlying expression of the phase. What does it represent?
by mika
22 Jan 2020, 13:18
Forum: ElmerSolver
Topic: Simulation of the force between two magnets
Replies: 5
Views: 77

Re: Simulation of the force between two magnets

Hi, First, it seems that the attached grd-file doesn't produce a sensible numbering of boundaries to assign boundary conditions correctly. I'm attaching a modified file which doesn't produce overlapping parts of the boundary. Note also that here the right symmetry BC is the do-nothing condition (the...
by mika
21 Jan 2020, 18:21
Forum: ElmerSolver
Topic: 2d simulation of acoustic wave propagation
Replies: 38
Views: 769

Re: 2d simulation of acoustic wave propagation

Are you sure about the coordinate dependence in the MATC expression? When the dependence is on the coordinate variable, the following correspondence holds (note that the first index is 0): tx(0) = x, tx(1) = y and tx(2) = z. Now you define the dependence on the z-coordinate which is zero everywhere,...
by mika
17 Jan 2020, 17:46
Forum: ElmerSolver
Topic: Simulation of the force between two magnets
Replies: 5
Views: 77

Re: Simulation of the force between two magnets

Hi,

In the sif file the magnetization vectors seem to have the same sign. Should we change one sign to be consistent with your description of the problem? The magnitude of the magnetization vector is 8e5 in the sif, while 8e7 in the message?

-- Mika
by mika
17 Jan 2020, 11:27
Forum: ElmerSolver
Topic: Non-zero divergence with MgDyn
Replies: 4
Views: 47

Re: Non-zero divergence with MgDyn

Extracting accurate derivative information from the lowest-order accurate B-field (for the lowest-order elements the L2 error of B with respect to the mesh size parameter h is expected to be of order h) can also be a challenge. Hence I'd try with the second order basis functions (by setting "Quadrat...
by mika
16 Jan 2020, 11:54
Forum: ElmerSolver
Topic: Non-zero divergence with MgDyn
Replies: 4
Views: 47

Re: Non-zero divergence with MgDyn

Hi, At least one issue here should be that the fields which are available within Paraview and are generated from the primary FE solution are not an exact representation of what is available within the primary solver. Especially with the curl-conforming basis functions which are employed when the AV-...
by mika
15 Jan 2020, 11:24
Forum: ElmerSolver
Topic: 2d simulation of acoustic wave propagation
Replies: 38
Views: 769

Re: 2d simulation of acoustic wave propagation

What I did say was that Paraview shows me a vector-valued variable "Pressure Wave" whose X-component and Y-component correspond to "Pressure Wave 1" and "Pressure Wave 2" referenced in the sif file. So I get neither "Pressure Wave 1" nor "Pressure Wave 2" directly. If one necessarily needs these nam...
by mika
14 Jan 2020, 17:49
Forum: ElmerSolver
Topic: 2d simulation of acoustic wave propagation
Replies: 38
Views: 769

Re: 2d simulation of acoustic wave propagation

The standard iterative solvers for the Helmholtz problem at a high wavenumber are generally known to be ineffective unless a special preconditioner is devised. Perhaps the Comsol result was based on a direct solver. You might also try the same approach and use a direct (MUMPS) solver, if installed, ...