# Magnetic-Mechanic Coupling¶

In this tutorial we consider an axi-symmetric model of a coil and a plate as depicted in the figure. The inner and outer radii of the coil, $r_1$ = 0.0025 m and $r_2$ = 0.0075 m. The length of the coil, $l_1$ = 0.008 m. The plate thickness and air gap is $l_2$ = 5 $\cdot 10^{-4}$ m respectively $l_3$ = 7.5 $\cdot 10^{-4}$ m. The point $C$ is located in the center of the coil, the point P in the middle of the plate at $z$ = 0.005 m. The plate is either made from iron or aluminum, with electric conductivity and linear magnetic permeability given in the mat.xml. The coil has 40 turns and is fed by a controlled current of $i$ = 10 kA. 1. Create a mesh using Cubit and geometry.jou (Hint: you can use the command cubit -batch -nojournal -nographics geometry.jou to create the mesh with the terminal.)
2. Simulate the transient magnet with openCFS and use the following input files: coil_transient.xml and amt.xml

## Tutorial Suggestions¶

• Look at the magnetic field lines ( with paraview: stream trace)
• Have a look at the iterative coupling section in coil_transient.xml
• Visualize the time signal of the z-displacements of point $P$ for both plate-materials in one figure
• Plot the displacement of the plate for both plate-materials.
• Describe the time signals: Are there transient effects? What is the difference between the amplitudes with aluminum and iron plate and why is there a difference?

## Further examples in the testsuite¶

If you need more examples, please have a look at our examples from the testsuite