Ansys Maxwell: 3D Eddy Current Analysis

Hello everyone, this is Adel from Ozen Engineering. In this video, I'll show you a simple Ansys Maxwell example using the Eddy Current solver to calculate the ohmic loss on a disk above a coil. I'll start by changing the solution type to Eddy Current and I'll set the model units to centimeters.

Now, let's draw our coil using a user-defined primitive. So, I'll go to segmented helix and select polygon helix. I'll set the polygon radius to 1.5 cm and the start helix radius to 1.5 cm, the radius change to 3.1 cm, the pitch to 0, and the number of turns to 8. I click OK.

Now, if I double-click on Polygon Helix1, we can rename it Coil. I'll set the material to Copper, and I'll change the color to Yellow. Here, I click OK. Now, let's draw a box.

I'll set the position to 14, 0, minus 2 centimeters, the x-size to 2, the y-size to 2, and the z-size to minus 2 centimeters. Now, let's create the second box. I set the position to 40.5, 0, minus 2 centimeters. I set the X size to 2, the Y size to 2, and the Z size to minus 2. Click OK.

Okay, and now we need to connect the box surfaces facing each other, so I'll go to the face selection mode. Let's select both, right-click, go to Edit Surface, Create Object From Face. Now, right-click again, Go to Edit Surface, Connect.

Let's now select Box 1 and Box 2, Right-click, go to Edit, Duplicate Along Line, and set the vector to 0 0 1 cm, and click OK. Now, let's go back to the Object Selection mode, and select all the objects, then click Unite. This is the coil final geometry.

And now, let's create the disk by drawing a regular polyhedron. I will set the center position to 0, 0, 1.5 cm and the start position to 4, 0, 1.5 cm.

I'll set the height to 1 cm and the number of segments to 36. Let's rename this disk and set the material to Cast Iron, and I'll change the color to Orange. In the next step, we'll create the coil terminal by using the section option.

So, I'll select the coil, go to Edit, Surface, Section, and we will select the YZ plane. Click OK. Let's rename this.

Let's start with the coil terminal, and with this coil terminal selected, let's right-click and go to Edit, Boolean, Separate Bodies, and here we'll delete all those objects except for the coil terminal. I'll select it, right-click, and go to Assign Excitation.

Here, with the type set to Solid, I set the current peak value to 125 amperes. And click OK. Now, for the Cast Iron plate, the skin depth is around 0.24 centimeters. To resolve it effectively without adding mesh operations, we will create surfaces at a depth of 0.125 cm and 0.25 cm.

This will ensure that we have at least two layers of mesh elements in the skin region. So, let's go and select this face on the disk. Right-click, go to Edit, Surface, Create Object From Face. Right-click again, go to Edit, Arrange, Move, and I'll move it by 0.125 cm on the Z-axis. And click OK.

Now, let's right-click again and go to Edit, Duplicate Along Line, and here I'll set the vector to 0.125 centimeters on the z-axis and click OK. Now, let's create the region. So, I'll draw a cylinder.

I'll set the center position to 0, 0, minus 1, I'll set the radius to 15 cm and the height to 10 cm, and I'll set the number of segments to 36, then click OK. Now, let's double-click on Cylinder 1, I'll rename it Region and check Display Wireframe and click OK.

To turn on any current calculation, let's go to Excitation, right-click on it, and go to Set Eddy Effects. And here, I'll select Eddy effect only for the disk, and click OK.

Now, let's add a solution setup, so right-click on Analysis, Add Solution Setup, and I set the maximum number of passes to 15, the percent error to 2. Let's go to Conversions, here I'll reduce the refinement per pass to 20%. And under Solver, I'll set the adaptive frequency to 500 Hz, and click OK.

Now, we can run a validation check and run the model by clicking Analyze All. Once the simulation is complete, we can go and view the results. First, I'll plot the mesh on the disk, so I'll select it, right-click, go to Plot Mesh, and done.

Here, you can see the effect of the automatic adaptive meshing and also the effects of the mesh seeding. So, here we have a denser mesh near the bottom of the disk where the extra layers were inserted. Now, let's open the Fields Calculator and calculate the ohmic loss on the disk.

So, I'll go to Quantity, select Ohmic Loss, then Geometry, select Disk, click Integrate, then Evaluate. And here, you can see that the ohmic loss is around 254 watts. Now, let's hide the mesh. I'll select the disk, right-click, go to Fields, and I'll plot the current density vector.

Here, I'll check Plot on Surface Only, and click Done. Let's also plot the ohmic loss distribution, so I'll select the disk, go to Fields, Other, and select Ohmic Loss. Here, I'll check Plot Surface Only, click Done. And here's our ohmic loss distribution in watts per cubic meter.

In this video, we saw an Ansys Maxwell example using the Eddy Current Solver to calculate the ohmic loss on a disk above a coil. Thanks for watching, and see you in the next video. Please contact us at https://ozeninc.com/contact for more information.