Default Settings of Particle Dynamics
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Re: Default Settings of Particle Dynamics
Can you post the working test model sif and mesh?
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Re: Default Settings of Particle Dynamics
The jump in a single step is nearly the same regardless of the time step (1e-15 to 1e-9) which makes me think it's something about the mesh or spawn conditions.
For example:
For example:
Code: Select all
MAIN:
MAIN: -------------------------------------
MAIN: Time: 1/20000: 1.000E-15
MAIN: -------------------------------------
MAIN:
ParticleDynamics: -----------------------------------------
ParticleDynamics: Following the path of the particles
Statistical info on current coordinate values
Mean: 3.4500000699913172E-002 -6.4860928685100937E-010 -4.8856527129484508E-010
Abs: 3.4500000699913172E-002 3.9033122218275929E-009 3.7219216500204368E-009
Var: 4.5625301874860709E-009 4.7380696194091742E-009 4.4414509352605569E-009
Min: 3.4499991563837581E-002 -8.6450825131470156E-009 -8.6598595886241417E-009
Max: 3.4500008662648386E-002 8.5945020326808508E-009 8.1028555946225105E-009
Statistical info on current velocity values
Mean: 0.0000000000000000 0.0000000000000000 0.0000000000000000
Abs: 0.0000000000000000 0.0000000000000000 0.0000000000000000
Var: 0.0000000000000000 0.0000000000000000 0.0000000000000000
Min: 0.0000000000000000 0.0000000000000000 0.0000000000000000
Max: 0.0000000000000000 0.0000000000000000 0.0000000000000000
ParticleOutputVtu: Saving in VTK XML unstructured format to file: particles.vtu
Statistical info on current coordinate values
Mean: 6.2997818918521017E-003 -2.8887769726496839E-003 -7.5848444277543489E-005
Abs: 1.2591389584284213E-002 6.4008375800768047E-003 9.9370754269542914E-003
Var: 1.5063945515253769E-002 1.0141367023783468E-002 1.2840787990134817E-002
Min: -1.9389048062423943E-002 -2.8829138497424231E-002 -1.9845399150312314E-002
Max: 3.4500008662647984E-002 2.1189775091820767E-002 2.1009812736142840E-002
Statistical info on current velocity values
Mean: -7.4044194727076865E-002 -4.3445609568104736E-003 2.7900404856991589E-002
Abs: 8.3251891993981836E-002 8.5805204413712567E-003 4.8344696060490168E-002
Var: 0.15837987831572073 1.5965178519418165E-002 9.6362636908131433E-002
Min: -0.48195943455625362 -5.4163471571248449E-002 -0.14354608453801862
Max: 5.9486034454402807E-002 2.6772353932426361E-002 0.29086333977545364
ParticleDynamics: All done
ParticleDynamics: -----------------------------------------
Last edited by willsprocket on 25 Jun 2022, 01:51, edited 1 time in total.
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Re: Default Settings of Particle Dynamics
It seems like it's a problem with the mesh being second order. If I switch to 1st order meshing it works as expected. I thought 2nd order would produce much higher quality results, but maybe it isn't stable numerically and a different method should be used to solve it? I would really appreciate hearing thoughts!
Last edited by willsprocket on 25 Jun 2022, 06:05, edited 2 times in total.
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Re: Default Settings of Particle Dynamics
Also, it would be great if the electric field could be solved steady-state than referenced in a transient simulation and not saved at every step. My simulations are creating a ridiculous number of files of redundant information.
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Re: Default Settings of Particle Dynamics
False victory. Upon further work, the 1st order mesh doesn't work. The particles still jump in the first timestep.
I've tried the following but there is no change:
Will
I've tried the following but there is no change:
Code: Select all
Timestep Distance = Real 1e-4
Max Characteristic Speed = Logical True
Min Timestep Size = Real 1e-15
Max Timestep Size = Real 1e-10 ! Same as simulation setting
Max Timestep Intervals = 25
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Re: Default Settings of Particle Dynamics
It seems like there are some portions of the mesh that cause the first step to jump. I think the solver thinks the particle isn't in a valid portion of the mesh. The electrostatic field looks smooth and continuous throughout the entire domain.
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Re: Default Settings of Particle Dynamics
More testing shows there are regions of the mesh that the particles just don't travel through correctly.
The electric field is as expected everywhere.
Could mesh face orientation be a problem? Could the mesh numbering be all meshed up?
I also get a weird warning when using parallel solve, something about a charged particle boundary condition. The particle motion in some regions is completely non-physical with a partitioned mesh and some particles have the jump on the first step.
The electric field is as expected everywhere.
Could mesh face orientation be a problem? Could the mesh numbering be all meshed up?
I also get a weird warning when using parallel solve, something about a charged particle boundary condition. The particle motion in some regions is completely non-physical with a partitioned mesh and some particles have the jump on the first step.
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Re: Default Settings of Particle Dynamics
Hi,
Parallel operation has been tested much less than the serial one. There has not really been that many active users for this and I think most have been content on serial. Perhaps you could test the serial operation 1st.
There are tons of flags for this. It really does not make sense to save the potential field every time step. Just save the "vtu" files once and use the separate particle output routine to save the particles when you need them.
-Peter
Parallel operation has been tested much less than the serial one. There has not really been that many active users for this and I think most have been content on serial. Perhaps you could test the serial operation 1st.
There are tons of flags for this. It really does not make sense to save the potential field every time step. Just save the "vtu" files once and use the separate particle output routine to save the particles when you need them.
-Peter