Magnetic field generated by a magnet assembly for use in magnetic refrigeration

Magnets

Magnets are used in many different technologies for storage and conversion of energy. Magnetic bearings with very low friction can be used in flywheels which store kinetic energy. And when the rotational energy of a wind turbine is converted to electricity, giant generators containing magnets are used.

Magnetic fields can be created either by magnetic materials (permanent magnets) or by an electrical current (electromagnets). At DTU Energy we do research on both permanent magnet systems and superconducting magnets, where the magnetic field is created by a current in a superconducting material.

Our main focus is the design and modelling of magnet structures where a number of magnets are combined to create a magnetic field with specific properties. The aim can be to create a very homogeneous field in a certain volume; such magnets can by used for nuclear magnetic resonance, e.g. in MRI scanners for medical purposes. Another example is to design a magnet creating volumes with a very high magnetic field alternating with volumes with almost no field. This is the aim when developing a magnet for magnetic refrigeration.

We also work with characterization of materials, one object being to find ways to recycle magnets. Another important topic is to understand the connection between materials properties and the properties of the final magnet. This we investigate both experimentally and by micromagnetism models.

Some important research topics are:

  • Modelling of magnet structures for generating extremely homogeneous fields
  • Manufacture and modelling of superconducting tapes and coils
  • Modelling of magnetic materials on the microscale (1-50 micrometer)
  • Modelling and optimization of magnet structures, e.g. using new methods based on machine learning
  • Investigations and modelling of the interplay between magnetism and heat transport in magnetocaloric materials.

 

Contact

Kaspar Kirstein Nielsen
Associate Professor
DTU Energy
+45 46 77 47 58