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simple_electrostatic_simulation_in_femm_-_step-by-step_tutorial [2021/05/11 21:13]
stanzurek [Step 11 - block labels, materials, currents] 		simple_electrostatic_simulation_in_femm_-_step-by-step_tutorial [2021/05/11 22:08] (current)
stanzurek [Step 19 - that's it!]
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 {{enter_point.png}} Fig. 3-2. Entering point with coordinates (0,0) {{enter_point.png}} Fig. 3-2. Entering point with coordinates (0,0)
  
-Click on the ''Zoom extents'' button (Fig. 3-3), which is the third one (white rectangle with a magnifying glass). (//If not sure - hover a mouse over the buttons and see their description in the botoom left of the FEMM window.//) +Click on the ''Zoom extents'' button (Fig. 3-3), which is the third one (white rectangle with a magnifying glass). (//If not sure - hover a mouse over the buttons and see their description in the bottom left of the FEMM window.//) 
  
 Then click on the ''Zoom out'' button once (magnifying glass with a minus). Then click on the ''Zoom out'' button once (magnifying glass with a minus).
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 If some block label was left undefined then this message will say something like:  If some block label was left undefined then this message will say something like: 
  
-| //Created mesh with 12239 nodes.// \\ //Grey mesh lines denote regions that have no block label.//  |+| //Created mesh with 11957 nodes.// \\ //Grey mesh lines denote regions that have no block label.//  |
  
 It is necessary to define ALL block labels. It is necessary to define ALL block labels.
  
-{{mesh.png?500}} Fig. 12-1. Mesh (automatically generated)+{{el/mesh_el.png?500}} Fig. 12-1. Mesh (automatically generated)
  
 ---- ----
 ==== Step 13 - analyse / solve ==== ==== Step 13 - analyse / solve ====
  
-Analysis is executed by clicking the "cranked cog" icon (red arrow in Fig. 13-1). A pop-up window appears which shows the progress of calculations. Just wait until it finishes. No message is shown if all finishes correctly. +Analysis is executed by clicking the "cranked cog" icon (red arrow in Fig. 13-1). A pop-up window appears which shows the progress of calculations. Just wait until it finishes. No message is shown if all finishes correctly, which for small models it can be less than 1 second. 
  
-As soon as the small window dissapears the results can be viewed by clicking the "glasses" button (black arrow).+As soon as the small window disappears the results can be viewed by clicking the "glasses" button (black arrow).
  
 +If there are errors in the model or material data the solution might not converge. If the computation time is excessive typically there is a problem somewhere in the model (block labels, double labels, wrong boundary, etc.)
  
-For all-linear models the calculation finishes in one step. For non-linear models it takes many iterations. For highly non-linear models (e.g. with deep saturation) or with large very dense mesh, the calculatiations can take very long time.  +{{el/analyse_el.png?500}} Fig. 13-1. Analyse / solve
- +
-If there are errors in the model or material data the solution might not converge. If the computation time is exessive typically there is a problem somewhere in the model (block labels, double labels, wrong boundary, etc.) +
- +
-{{analyse.png?500}} Fig. 13-1. Analyse / solve+
  
 ---- ----
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 These two options can be accessed also through: ''menu > View > Contour plot'' and ''menu > View > Density plot''. These two options can be accessed also through: ''menu > View > Contour plot'' and ''menu > View > Density plot''.
  
-{{solution1.png?500}} Fig. 14-1. Results window, with field lines, no colour map+{{el/solution1_el.png?500}} Fig. 14-1. Results window, without equipotential lines, and colour map
  
-Clicking the "rainbow" button shows the small window, which which the type of variable can be selected: Flux density B, Magnetic field intensity H, or Current density J. Limits are scaled automaticaly betwen the min. and max. value present in the model, but they can be adjusted manually as needed, Fig. 14-2.+Clicking the "rainbow" button shows the small window, which which the type of variable can be selected: Voltage V, Flux density D, or Field intensity E. Limits are scaled automatically between the min. and max. value present in the model, but they can be adjusted manually as needed.
  
 Don't forget to tick the "Show Density Plot" box! Don't forget to tick the "Show Density Plot" box!
- 
-{{solution2.png?500}} Fig. 14-2. Choosing Flux density B |T| density plot 
- 
-Flux density |B| plot with the flux lines disabled is shown in Fig. 14-3. 
- 
-{{solution3.png?500}} Fig. 14-3. Flux density |B| plot 
  
  
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 ==== Step 15 - plot data along line ==== ==== Step 15 - plot data along line ====
  
-In the solution window, use the "red line" icon (Fig. 15-1) to draw a path of lines or arcs, between any two existing points (left-click of mouse) or between any arbitrary points (righ-click of mouse). Once the path is created, various values can be plotter along that line, from the beginning to its end, in the same order as it was drawn.+In the solution window, use the "red line" icon (Fig. 15-1) to draw a path of lines or arcs, between any two existing points (left-click of mouse) or between any arbitrary points (right-click of mouse). Once the path is created, various values can be plotter along that line, from the beginning to its end, in the same order as it was drawn. 
 + 
 +Use "line" icon (red arrow), draw the line between the points of interest, then click on the "graph" icon (black arrow), and select the type of plot in the pop up window.
  
 The path can end at the same point it started. The path can end at the same point it started.
  
-To plot, press the "graph" icon (Fig. 15-1). A pop-up window will open and the variable to be plotted can be selected, Fig. 15-2. N+To plot, press the "graph" icon (Fig. 15-1). A pop-up window will open and the variable to be plotted can be selected. The graph will be plotted in a new window.
  
 Note that there is an option to export/write the data to a file, which can be then used with any spreadsheet software. Note that there is an option to export/write the data to a file, which can be then used with any spreadsheet software.
  
-{{graph_of_line.png?500}} Fig. 15-1. Draw path to plot data+{{el/line_el.png?500}} Fig. 15-1. Draw path to plot data
  
  
-{{graph_js_plus_je.png}} Fig. 15-2. Select data to plot or export to file+{{el/line_el2.png?500}} Fig. 15-2. Plotted graph
  
-The graph will be opened in a new window. For AC simulations, black curve means the absolute value (total amplitude), blue is the "real" component (0 deg), and green is the "imaginary" component (90 deg).+---- 
 +==== Step 16 - line integral ====
  
-{{eddy_current_graph.png?500}} Fig. 15-3. New window with plotted data+Some values can be integrated over lines or blocks. Draw a line, and then chose the integral icon, Fig. 16-1.
  
----- +The calculated voltage is exactly -1 V, as defined in the conductors. Because the line was drawn from left to right, from "zero" to "positive", so the integral is evaluated correctly.
-==== Step 16 - block integral ====+
  
-Some values can be integrated over the whole blocks. To select a block use the "green square" button, and then click anywhere within a block of interest, Fig. 16-1.+{{el/line_integral_el.png?500}} Fig. 16-1. Select block
  
-Then click on the "integral" icon. 
  
-{{block_integral1.png?500}} Fig. 16-1. Select block 
  
-A pop-up window will appear (Fig. 16-2), and the drop-down list can be used to select the value of interest. After accepting, the value will be evaluated and shown in another pop-up window, Fig. 16-3. 
  
-{{block_integral2.png}} Fig. 16-2. Select type of integral  
- 
-{{block_integral3.png}} Fig. 16-3. Calculated value of integral 
  
 ---- ----
 ==== Step 17 - conductor info ==== ==== Step 17 - conductor info ====
  
-The losses in the ciruict (energised coil) can be integrated with the block method described above, but much reacher information is provided with the "Circuit properties" icon, Fig. 17-1. +Info about the given conductor with the "Conductor properties" icon, Fig. 17-1.  
 + 
 +If there is more than one conductor defined then it can be selected from the drop-down list.
  
-If there is more than one current/circuit defined then it can be selected from the drop-down list.+Capacitance is charge over voltage, C = q/V, and because the voltage was set to 1 V, the capacitance of this capacitor is 3.6e-13 F, or 0.36 pF.
  
-{{conductor_info.png?600}} Fig. 17-1. Circuit properties+{{el/conductor_properties_el.png?600}} Fig. 17-1. Conductor properties
  
 ---- ----
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 If snap-to-grid is enabled then only the grid positions will be available. If snap-to-grid is enabled then only the grid positions will be available.
  
-{{data_at_any_point.png}} Fig. 18-1. Click anywhere to get values+{{el/point_props_el.png}} Fig. 18-1. Click anywhere to get values
  
 ---- ----
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 ==== Step 19 - that's it! ==== ==== Step 19 - that's it! ====
  
-And that's all - now you can run a simple FEMM magnetics simulation!+And that's all - now you can run a simple FEMM electrostatic simulation!
  
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simple_electrostatic_simulation_in_femm_-_step-by-step_tutorial.1620760420.txt.gz · Last modified: 2021/05/11 21:13 by stanzurek

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