Dear Daniel,
I am geting tired of comsoling... because I do not know anymore what I can do to make my models converge.
i started with the waveguide microwave plasma from the model-library. I put some substrate under bias within the plasma region.. so far it is working, even if it is already a tough calculation that needs 2 days.
whenever some e-temperature spikes occurs, then the timestepping gets very small, that is OK, it needs smoothing. so increasing the mesh density seems to be a solution to prevent this.
but my design is even more complicated since the microwave has to move (propagate) in the DC sheath..
the models run up to 10e-5 sec or so when the plasma reaches cut-off density and the fields get expelled from the plasma region, the ion currents make a big jump... but then it tells me after some days that the convergence fails, and the time increased some 10e-7 sec within the last 2 days.. the convergence plots has a plateau around 10e-08/10e-9.. I have really the suspiscion that the solver starts to look at each GHz oscillation !!!
what I can I do to have different solver conditions for the 2 segregated steps: the one for the plasma (heavy species and electrons) and the other for the E-fields..
the E-field solver should be very fast.. 1 or 2 iteration should be enough.. how to set this?
when I used the mwp models only, it is possible to have a solution within a day.. but not when I include the electrical potential..
one strange thing happened when I had a circuit with the ballast resistor and the bolcking capacitor (like in the pdf library model of the 2D-DC column).
my voltage at the capacitor was increased beyond the DC-voltage level? how to explain that?
Mr. Tong at Kesco (Japan) is trying to support me, but he tells me to keep the bias voltage low (50V) as well as the pressure (beyond 30 Pa).. but that is not the real world.. 400 to 500V are needed and 60 to 100 Pa.
(at the low pressures the cutoff may not be reached, and at low voltages the running of the microwave in the dark-space doesn't work)
do I have the go to the model-builder a have my own module? is the mwp module missing some important physics my set-up requires? (or do we miss the AC/DC modul for that problem? I run RF and PLASMA only)
thank You very much for the support.
Lukas Alberts
Nagoya University
I am geting tired of comsoling... because I do not know anymore what I can do to make my models converge.
i started with the waveguide microwave plasma from the model-library. I put some substrate under bias within the plasma region.. so far it is working, even if it is already a tough calculation that needs 2 days.
whenever some e-temperature spikes occurs, then the timestepping gets very small, that is OK, it needs smoothing. so increasing the mesh density seems to be a solution to prevent this.
but my design is even more complicated since the microwave has to move (propagate) in the DC sheath..
the models run up to 10e-5 sec or so when the plasma reaches cut-off density and the fields get expelled from the plasma region, the ion currents make a big jump... but then it tells me after some days that the convergence fails, and the time increased some 10e-7 sec within the last 2 days.. the convergence plots has a plateau around 10e-08/10e-9.. I have really the suspiscion that the solver starts to look at each GHz oscillation !!!
what I can I do to have different solver conditions for the 2 segregated steps: the one for the plasma (heavy species and electrons) and the other for the E-fields..
the E-field solver should be very fast.. 1 or 2 iteration should be enough.. how to set this?
when I used the mwp models only, it is possible to have a solution within a day.. but not when I include the electrical potential..
one strange thing happened when I had a circuit with the ballast resistor and the bolcking capacitor (like in the pdf library model of the 2D-DC column).
my voltage at the capacitor was increased beyond the DC-voltage level? how to explain that?
Mr. Tong at Kesco (Japan) is trying to support me, but he tells me to keep the bias voltage low (50V) as well as the pressure (beyond 30 Pa).. but that is not the real world.. 400 to 500V are needed and 60 to 100 Pa.
(at the low pressures the cutoff may not be reached, and at low voltages the running of the microwave in the dark-space doesn't work)
do I have the go to the model-builder a have my own module? is the mwp module missing some important physics my set-up requires? (or do we miss the AC/DC modul for that problem? I run RF and PLASMA only)
thank You very much for the support.
Lukas Alberts
Nagoya University