Being able to compute the spatial gradients of the magnetic field or magnetic flux density is needed in areas such as radiology, magnetophoresis, and geophysics. One of the most important applications is in the design of magnetic resonance imaging machines, where it’s important to analyze not only the field strength, but also the spatial variation of the field. Today’s blog post demonstrates how to compute and plot the gradients of the magnetic field in 3D electromagnetic simulations in COMSOL Multiphysics.