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feynman1
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How to visualize charge distributions in COMSOL, like showing + or - charges on a surface or a bulk in postprocessing?
Thanks. That's a continuous distribution. What if I want to show discrete +/- charges?DrClaude said:Make a surface plot of the space charge density (es.rhoq).
There are no such things as discrete charges in the equations being solved, only a charge density.feynman1 said:Thanks. That's a continuous distribution. What if I want to show discrete +/- charges?
Right. So I assume there's no such feature of visualizing as point charges. Point charges look more intuitive than surface distributions.DrClaude said:There are no such things as discrete charges in the equations being solved, only a charge density.
I dint understand. Do you mean polarization of a dielectric?feynman1 said:Is there a feature of showing induced bound charges?
Yes, showing bound charges of a dielectric, caused by polarization.DrClaude said:I dint understand. Do you mean polarization of a dielectric?
Is the purpose of this for your internal 'understanding' or is it for the purpose of presenting ideas to others? I could see that a graphic of +and - charges could be familiar for people who are not well informed on the topic but why, as you are clearly familiar, would you want to go for a dumbed-down presentation? Presenting charge density as areas with random + or - signs scattered around could actually end up in a mess of symbols - if you actually want a hint of the quantitative situation. Just try it yourself, putting signs on a diagram, by hand. Is the result satisfactory?feynman1 said:How to visualize charge distributions in COMSOL, like showing + or - charges on a surface or a bulk in postprocessing?
Kind of both. Would be nicer to show them in the simulation directly, without myself plotting them.sophiecentaur said:Is the purpose of this for your internal 'understanding' or is it for the purpose of presenting ideas to others? I could see that a graphic of +and - charges could be familiar for people who are not well informed on the topic but why, as you are clearly familiar, would you want to go for a dumbed-down presentation? Presenting charge density as areas with random + or - signs scattered around could actually end up in a mess of symbols - if you actually want a hint of the quantitative situation. Just try it yourself, putting signs on a diagram, by hand. Is the result satisfactory?
Yes - of course. But you can see the result for yourself with just one example. Perhaps, rather than spending effort on producing an inferior display system, you could work on a way to explain what the available charge distribution display shows. It's clearly so much more informative that I'm sure you could convince even the most reactionary audience.feynman1 said:without myself plotting them.
You can plot the polarization of the material.feynman1 said:Yes, showing bound charges of a dielectric, caused by polarization.
yes, one can plot polarization. nice to plot a finite number of +- charges to represent a surface distribution, if possible.DrClaude said:You can plot the polarization of the material.
To add to what @sophiecentaur said, it would be could for you to learn to interpret the results by looking only at the charge density or the polarization. Using + and - charges may be good for pedagogical purposes (I do use that when I teach), but you'll go farther by being able to lose those training wheels!
Remember also that the actual discrete charges are electrons and ions. Any accurate representation of the charges would include so many of them as to lead back to what you see using a surface plot...
To visualize the charge distribution in COMSOL, you can use the "Charge Density" plot type in the Results tab. This will show the distribution of electric charge in your simulation model.
Yes, you can change the color scale for the charge distribution plot by right-clicking on the plot and selecting "Properties." In the Properties window, you can adjust the color scale under the "Color" tab.
You can use the "Probe" tool in COMSOL to see the charge distribution at a specific point in your simulation model. Simply click on the Probe tool and then click on the point of interest in your model.
Yes, you can animate the charge distribution in COMSOL by using the "Time" plot type in the Results tab. This will show the change in charge distribution over time in your simulation.
Yes, you can export the charge distribution plot from COMSOL by right-clicking on the plot and selecting "Export." You can choose the desired file format and save the plot for use in other programs.