Speaker
Description
Many neutron instruments use strong magnetic fields as part of their standard sample environment. Such magnetic fields are currently generated with cryomagnets, which typically produce a strong stray field due to their design. Neutron instrument components such as the sample stage, motors and electronics are often exposed to this magnetic stray field and can be damaged as a result. Additionally, strong attractive forces can act on the cryomagnet and cause it to quench. This occurs when steel parts are in the stray field and a maximum permissible force of attraction is exceeded. Quenching can be prevented with proper design measures. Therefore, when designing neutron instruments, magnetic fields and their effects should be taken into account.
In order to quickly identify potential damage to motors and electronics, design engineers need a tool that allows them to calculate local magnetic fields during instrument design. The tool should also be able to calculate magnetic attraction forces to predict or prevent quenching of the cryomagnet. Unfortunately, good magnetic field calculation programs are usually difficult to use and require specialized knowledge. Moreover, the development of a suitable calculation model is time-consuming.
To address the aforementioned gap in the designer's toolbox, an easy-to-use software application is presented. It is a so-called COMSOL app that was developed at LIN* in 2024. Using the finite element method, it quickly and efficiently calculates magnetic fields and their effects. The tool is tailored to neutron instrumentation.
*Laboratory for Neutron and Muon Instrumentation (LIN), Paul Scherrer Institut, Switzerland
