Optimization of a Quadrupole Magnet with the 3DEXPERIENCE Platform and CST Studio Suite

Magnet design covers many disciplines of physics, and a unified model for magnet design would have many benefits in accelerating and streamlining the magnet development process. The workflow presented in this blog post allowed a quadrupole magnet to be designed with CATIA, simulated with SIMULIA CST Studio Suite and optimized with Process Composer. This workflow was performed all in one common environment, the 3DEXPERIENCE platform.

By Ben Pine

Engineers have long sought a concept for a single unified model for design of a magnet. Any meaningful virtual twin model must embody the ability to simulate the electromagnetic, thermal and structural performance of the device, as well as retaining the full geometric, materials and manufacturing information. The virtual twin must be able to respond to a design change and either identify which simulations must be repeated to capture the effect of the design change. As a minimum, it should reliably identify that if simulation results were produced from a previous version of the virtual prototype. The ability to optimize the design accounting for input from multiple areas of physics is also paramount.

This blog post reports how the 3DEXPERIENCE platform has been used to couple CAD using the Mechanical Designer role, electromagnetic simulation tools CST Studio Suite® and Opera®, and optimization capabilities provided by Process Composer. In this connected workflow, the profile of the steel poles of an electromagnetic quadrupole were designed and parametrized using the Mechanical Designer role. The parametrized design was then used as the basis for an optimization, and the physics results were visualized through the 3DEXPERIENCE platform.

Design

A single pole of the magnet was first modeled using the CATIA app Part Design on the 3DEXPERIENCE platform. The pole was fully parameterized, particularly the pole tip that was to be the focus of the following optimization.

A three-part image. The first shows the sketch of the pole in Part Design. The second shows spline control points on pole tip. The third shows the sketch extruded to make the pole.
Figure 1: The design of a magnet pole in the CATIA Part Design app.
Simulation

Using the 3DEXPERIENCE platform, the part was imported into CST Studio Suite. Symmetry was used to create the rest of the quadrupole. Coils, mesh, boundary conditions and analysis options were added. The Magnetostatic solver was run and post-processing conditions defined.

A six-part image. First, pole geometry is imported to CST Studio Suite. Second, other features are added. Third, simulation is solved. Fourth, field is found on circle. Fifth, Fourier components are identified. Sixth, the solution is saved to 3DEXPERIENCE.
Figure 2. Setting up and solving the electromagnetic simulation of the quadrupole magnet.
Optimization

Optimization Process Composer was used to build an optimization process using CST Studio Suite driven by the parameterized CATIA geometry. Outputs from the CST Studio Suite model were used to set objectives for the optimization.

A six-part process. First, the CST app is added to the process. Second, CATIA parameters are available. Third, CST Studio Suite outputs are available. Fourth, design optimization is added to the process. Fifth, parameters are given bounds. Sixth, targets are provided for outputs.
Figure 3: Set-up of the optimization in Process Composer
Post-processing

Performance Studio was used to perform initial lightweight post-processing of the optimization results. From the initial results, a candidate geometry was selected.

A three-part process. First, a quick online analysis of results. Second, outputs are plotted against parameters. Third, the optimal candidate is loaded back to Part Design.
Figure 4: Selecting the optimal candidate.
Candidate Geometry

A CAD update of the candidate geometry was automatically performed in CST Studio Suite, and the resulting model re-simulated. It outperformed the initial model on all the relevant criteria.

The force generated on the poles and coils were calculated for subsequent mechanical evaluation. An initial calculation was made of the coil displacements.

A six-part process. First, CAD update is performed in CST. Second, results show saturation reduced. Third, template results are generated. Fourth, results show that Fourier terms reduced. Fifth, forces are calculated on coils. Sixth, the initial coil displacement calculation.
Figure 5: Verifying the optimized design and calculating structural performance.
Further Work

The next step of this analysis is to expand the multiphysics analysis. The forces from the electromagnetic simulation can be used to drive structural simulations using Abaqus roles on the 3DEXPERIENCE platform. These models can then be added to the optimization loop for a full multiphysics simulation. Ultimately, thermal simulations of electromagnetic losses can also be included.

Conclusion

Magnet design covers many disciplines of physics, and a unified model for magnet design would have many benefits in accelerating and streamlining the magnet development process. The workflow presented in this blog post allowed a quadrupole magnet to be designed with CATIA, simulated with SIMULIA CST Studio Suite and optimized with Process Composer. This workflow was performed all in one common environment, the 3DEXPERIENCE platform.

This approach promises reduced design times and optimal magnet performance. It also allows for a multiphysics approach to magnet analysis, with the magnet’s electromagnetic, thermal and structural mechanical properties – and the interaction between them – all considered at the same time.