Discussion Forum

Posted: 1 decade ago 2010年12月22日 GMT-5 15:42

Hi the phase angle you define in the main plot windows anly multiplies the solution by exp(i*phase*pi/180) so phase variable can be defined as the phase = atan2(imag(yourVariable),real(yourVariable))*180/pi the latter to have it in [deg] up to you to replace the yourVariable forthe one you want/need, no ? -- Good luck Ivar

Posted: 1 decade ago 2013年4月3日 GMT-4 05:13

Hi I,m new in Comsol and I have the similar question , kindly please help me to find the answer 1: How can plot voltage in phase (deg) , it means the x axis should be phase not time? 2: How can combine two plot together, it means, at first I plot voltage and phase then I want add charge and phase in the same plot ? Thanks in advance

Posted: 1 decade ago 2013年4月3日 GMT-4 11:08

Hi to set up your own data and equations use the DErived VAriable in the results section to populate one or several columns in the tables, then plot the tables. The physe of a signal is only there if your signal is a complex value (then expressed in a "phasor" representation. The phase of a complex value is obtained by the arg() operator (check the doc and use desired units, defaults rad) or the atan2(imag(my_var),real(my_var)) (my_var being the name of the complexe valued variable you want to express the phase of ... -- Good luck Ivar

Posted: 1 decade ago 2013年4月3日 GMT-4 11:45

Hi Ivar and Mike, from Mike's post I read that he wants to plot his result (displacement) as a function of phase, i.e. the phase along a full oscillation period should be the independent variable. If this is the case the solution would be to define the function exp(i*phase*pi/180) for 0

Posted: 1 decade ago 2013年4月3日 GMT-4 13:20

Hi Edgar Thanks for the precision, I see I'm skimmimg over the questions too quickly ;) -- Good luck Ivar

Posted: 1 decade ago 2013年4月3日 GMT-4 21:39

Thanks dear Ivar I have another question that: I want model the partial discharge (PD) in insulation , my geometry is insulation( rectangular) between two electrode with one void inside the insulation. I want model PD inside the void. or breakdown inside the void. anyway some problem that I faced is: 1: the conductivity of the void should be change while the electric field is increasing and then at certain value we will have breakdown, so how I can set the conductivity changeable with voltage and electric field? I have to use PDE form? for example: S= V*e^(U/U0)*E during discharge and otherwise S=S0 , how can i define this in comsol? 2: can we combine 2 physics together such as electrostatic and PDE? sorry for asking many question Thanks so much

Posted: 1 decade ago 2013年4月4日 GMT-4 01:28

Hi certainly you can combine about any physics / math nodes together, this is how COMSOL is built up, and too, its unique strength compared to any other tool I know about Just try it out, one or more physics for each domain, and correct BC (boundary conditions) per domain boundary, and this for ALL your dependent variables -- Good luck Ivar

Posted: 9 years ago 2015年5月8日 GMT-4 04:25

[QUOTE] Thanks dear Ivar I have another question that: I want model the partial discharge (PD) in insulation , my geometry is insulation( rectangular) between two electrode with one void inside the insulation. I want model PD inside the void. or breakdown inside the void. anyway some problem that I faced is: 1: the conductivity of the void should be change while the electric field is increasing and then at certain value we will have breakdown, so how I can set the conductivity changeable with voltage and electric field? I have to use PDE form? for example: S= V*e^(U/U0)*E during discharge and otherwise S=S0 , how can i define this in comsol? 2: can we combine 2 physics together such as electrostatic and PDE? sorry for asking many question Thanks so much [/QUOTE] Hi Im new to Comsol. My project is similar with you. Can I have some information how you model the insulation and what type of study did you used? I have difficulty to generate a graph (anything related to this). Can you help me? Thank you.

Posted: 8 years ago 2016年6月24日 GMT-4 19:09

Dear Edgar, I am relatively new to comsol, and it sounds like doing this should be trivial, but I cannot figure out how to plot some result in frequency domain (AC/DC module in my case, but it should be general post-processing tool) with the "phase" in the x-axis. Is there a direct simple way to make the phase the variable in the x-axis of the plot of a frequency domain result, without resorting to FFT study step, especially that I'm interested in a single frequency analysis? And is there an example in the application library to do it for a frequency domain study? Best regards, Majd